Is it too soon to jump into HTML5?

[deepsand]

The key is to plan for backward compatibility. The shims and polyfills, along with resets are all useful in the meantime until the standardization sets in. It will take lots of usage and development data to arrive at anything of a standard. We have to start using it now or the data will be skewed by the lack of it come 2014.

But, unless one is part of the formal development process, his data are invisible.

We're getting into the same bowl of spaghetti here that we're in re. CSS3. Everyone's implementing different selected pieces, and then claiming to be compliant with a standard that doesn't even exist. Hell, CSS3 looks to be another 20 years in the making.

[weegillis]

Compliance is really a subjective thing, I'll give you that, at this point. Old hatters who have built to standards all along are not going to go too far afield, but newbies coming out of the gate, with no background in standards are going to be taken for a loop over the coming years. And the web will continue to expand hodge podge all the way.

[mikmik]

Yes, I think it is best to wait until everyone is using html5 before testing the waters. Can't be to careful. /sarcasm
Only problem, people, is that no one cares if anything has been standardized; there is no such thing as a standardized way to render across all browsers. Does IE6, Safari, Opera, FF3.6-6.0, Chrome and IE's 7/8/9 all render CSS2.1 and HTML4 the same?
You can wait until you think HTML5 and CSS3 are *standardized* in three years, or whatever(6 months ago it was 2022), because one of the *standards* is that HTML5 is to be

At Mobile World Congress, W3C CEO Jeff Jaffe explained that the Last Call date typically means a standard is sufficiently stable for inclusion in products like browsers that are updated frequently - but that for it to become an official standard, W3C wants it to be "really hardened" so it can go into devices such as TVs or even automobiles that tend never to be updated.

One of the things holding it back, he said, is the lack of a sufficiently comprehensive test suite to fully test interoperability. Obviously, there are lots of test sites out there now, with different browsers looking better or worse depending on the test.

Jaffe said the 2011 browser releases have many innovative features and are likely to be very useful, but they may not support all of the features in the final HTML 5 standard. He also noted that W3C was interested in the broader "one web" concept, including new versions of the cascading style sheet (CSS) specification, scalable vector graphics (SVG), its new font framework, and a device API standard, so that browsers could access items such as geolocation from a phone through a consistent method.

Web sockets and the like of exact video parameters in the canvas element are the stuff of ongoing considerations for standardization and other esoterics. HTML has been ongoing revisions for 20 years and it is still going to be appended, even now, so it is a myth that you have ever used a standardizes implementation of html/xhtml anyways, and the majority of considerations that take so long to standardize are complex and technical as shown in the W3C HTML5 spec overview:
In addition to

The latter requirement in particular required that the scope of the HTML5 specification include what had previously been specified in three separate documents: HTML4, XHTML1, and DOM2 HTML. It also meant including significantly more detail than had previously been considered the norm
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It must be admitted that many aspects of HTML appear at first glance to be nonsensical and inconsistent.

HTML, its supporting DOM APIs, as well as many of its supporting technologies, have been developed over a period of several decades by a wide array of people with different priorities who, in many cases, did not know of each other's existence.

Features have thus arisen from many sources, and have not always been designed in especially consistent ways. Furthermore, because of the unique characteristics of the Web, implementation bugs have often become de-facto, and now de-jure, standards, as content is often unintentionally written in ways that rely on them before they can be fixed.
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The HTML specification published by the WHATWG is not identical to this specification. The main differences are that the WHATWG version includes features not included in this W3C version: some features have been omitted as they are considered part of future revisions of HTML, not HTML5; and other features are omitted because at the W3C they are published as separate specifications. There are also some minor differences. For an exact list of differences, please see the WHATWG specification.

Other things to consider:
Windows 8 is being designed around universal HTML5 deployment. (Web-connected and Web-powered apps built using HTML5 and JavaScript that have access to the full power of the PC/how developers will build apps for the new system. Windows 8 apps use the power of HTML5,)

Also, here is just one of many stories and reports I read every day:

When Apple's deadline to put up or shut up arrived on June 30, the Financial Times stuck around for an extra two months and then jumped iTunes' ship altogether to focus on its HTML5-based Web app.

Financial Times spokesman Tom Glover said that the paper is directing readers to the Web app, which he claims has 555,000 users--more users than on its native iOS apps combined and "now delivering the largest share of subscriptions from our mobile channels."

CEO John Ridding told PaidContent.org that the fallout wasn't solely about money and Apple's 30 percent slice of the pie, but that the Financial Times wanted sole ownership of the data it collects about its customers.

The question now is, who else is willing trash all association with iTunes? So far, a few companies have begrudgingly agreed to remove in-app purchasing options from their iOS products; some are becoming more focused on building HTML5 Web apps that can be read by mobile Safari.

Amazon, for instance, released the Web-based Kindle Cloud Reader, which skirts disagreeable policies and allows Amazon to keep 100 percent of its profits. Similarly, ebook retailer Kobo rebuffed Apple by building its own HTML5 ebook store.

Facebook is working on a new platform called Project Spartan, based entirely on HTML5. This is slightly odd given that Facebook isn't an e-commerce business. However, it could be seen as a punch in Apple's gut: if Facebook licenses the Project Spartan platform to developers, this could inspire many iOS developers to quit iTunes, and motivate product users to fire up mobile browsers and ignore neatly packaged apps.

This is from a year ago, and the situation has quite progressed since then: HTML5, open standards, and the BBC

For this reason we are committed to the aims of HTML5. In combination with CSS3 and Javascript it promises a step forward for the web. A truly interoperable experience would materially advance the capabilities we can offer to our audiences, by ushering in a new class of rich interactive experiences on the web. The benefits are not one dimensional. As HTML5 promises to allow us to create new online products with the confidence they will work across the web, the savings in our development and operating costs mean we can spend less on reversioning for different browsers and focus on product development. HTML5 can bring the web together in a way that will better allow us to serve our audiences and business partners.

Here's a good overview, Make Sure To Code My Site in HTML5

The vast amount of information available on the Internet and the increasing tech-savvy of today’s business owners is fostering a new understanding of web design, application development, social media, and more. But with all the information out there, make sure you separate the facts from the buzzwords. Continue reading ?
Filed under: Technology, Web, Web Design
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HTML and HTML5… Defined
There are a few reasons why asking someone to code “in HTML5” is not exactly correct. First and foremost, HTML5 is not a new coding language or a new framework to build websites on. HTML, or HyperText Markup Language, is a coding language that’s universal for the web. All web browsers read and interpret it. HTML5, for all intents and purposes, is a slang term for some new standards in HTML. There are some new tags (what’s a tag?) that are specific to HTML5, but the language is still the same HTML.
Currently, in March of 2011, as HTML5 is really starting to take hold, there are more and more places where it’s 100% acceptable to use the new tags. The most prominent place is mobile web.
But Back to the Question at Hand
Hopefully I haven’t insulted anyone who’s ever asked a developer to code their site in HTML5 because I truly love the interest in the web and in technology in general. My intention here is to clarify the little distinctions so that there’s no confusion down the road. A more appropriate question could be: “Can we (and should we) take advantage of the new features and technology offered by HTML5?” But don’t forget to follow that up with: “Will it still work in IE 6 on Windows XP, though?” Because of course: “My office only uses IE 6 and we can’t upgrade. I’m sure most of my clients are the same way, too.”

HTML5 is xhtml with added capabilities. There is nothing really to unlearn. It's just that mobile devices already account for something like 40% of internet usage, and is projected to go much higher.
"As smartphones like the iPhone and Android take over the mobile Web, the amount of data traffic going over cellular networks is expected to grow 40-fold over the next five years."
Mary Meeker: Mobile Internet Will Soon Overtake Fixed Internet

[Glen Lawrence]

On the bright side, jumping onto a coding base that won't be mainstream until 3 years later would give you a huge head start. Maybe HTML5 is not so bad after all, provided that it will actually gain momentum someday.

[weegillis]

On the bright side, jumping onto a coding base that won't be mainstream until 3 years later would give you a huge head start. Maybe HTML5 is not so bad after all, provided that it will actually gain momentum someday.

That 'someday' is already here. We don't have to look very hard to find lots of going concerns leading the way in their sector. It is stable enough right now to be put into most situations.

[Glen Lawrence]

I was referring to the idea of it being mainstream only in 2014. You raise a good point, though.

[alphaomega]

Most of people are just waiting until HTML5 is confidently ready. In the mean time, a browser sector and standard body are working on it..

Thank god not everyone is like most people. Nothing new would be ever invented and applied. Personally I do use HTML 5 and CSS 3 as much as I can understand it and apply it. I love what can by done with it and how light is the code.