Realize that it will take time for the search engines to increase your rankings.

Yes, this is certainly the dominant theme these days in Google and a sure-fire way to kill SERP spamming, but just how long is the big question.

IMO Google is shutting out too many good new sites because they aren't old enough. I've certainly seen SERPs favouring sites based on age, meaning it could take several years before you take your rightful place on page one (if you deserve it). In comparing one of my sites to its competitors I can see that we more than compete on ibl count, quality of ibls, on-page SEO and so on, yet languish 10 places below. We are only a year old, the others have been there 4, some haven't had any new content in years. In Yahoo and MSN the site ranks top five alongside those ranking similarly in Google.

So, in addition to the sandbox, I propose that there is certainly;

1. age filters on new links
2. some sort of consideration about age of domain and pages
3. a deliberate retardation on rankings of sites that have rising up the rankings too quickly
4. a favouring of sites that have occupied the top of the SERPs for a prolonged period - some sites just sit there and never move despite undertaking apparently no SEO activity

The waiting game can be very frustrating when you see old, stale sites above you that really don't deserve to be there.

Of course, the internet is a very dynamic thing and web technologies and content are evolving quickly, it seems counter-productive of Google to shut out the newer sites like this. Just because they are new doesn't mean they aren't relevant.