MSN Rankings Drop...like a rock!

[red]

I'm curious to know if anyone here at WPW has experienced the same type of drop in visitor traffic as I've experienced from MSN over the past 4-5 weeks.
I find it an odd coincidence that at about the same time MSN visitor traffic disappeared from my site MSN starting advertising their new PPC program VERY heavily.
My site is well established and has been around for nearly 7 years now. It has enjoyed very high rankings (#1-#4) for more than 200 keyword phrases for the past 3 years - virtually unchanged until a few weeks ago. The site, http://www.lockpickshop.com/ is still present in the index but natural rankings are ridiculously low.
Naturally I had to jump on the PPC bandwagon and start writing ads and bidding on keyword phrases to try to pick up some of the lost traffic. I believe in a healthy mix of natural and paid results but almost feel like I've been blackmailed into it by MSN.
Any thoughts, suggestions or conspiracy theories are welcomed (-:

[incrediblehelp]

I highly doubt (positive actually) that MSN would demote your organic rankings, now that your doing PPC with them.

So many other reasons could be involved for this drop. Any major changes recently to your website?

[red]

Of course I know that's true and it's just a weird coincidence. MSN is reputable. I'm just a bit paranoid.
I just signed on for the MSN PPC a couple of days ago and am still waiting for approval. None of my ads are even up yet.

To answer your question Incredible I did make some changes to the original pages and I am pretty certain that things will shake out reasonably soon.

Prior to the changes category page titles were named this way:
http://www.c-Pin-Kits.html

"C" prefix for category
"P" prefix for product

They were all shortened for better optimization by removing the "c-" prefix from the beginning of the category name to look like this:
http://www.lockpickshop.com/Pin-Kits.html

All 450+ product pages had been prefixed with a "p-"
and that was dropped at the same time so the product names stand out on their own better.

Each of the old pages have been redirected with 301's to the new pages.

The difference between MSN and the other 2 of the Big 3 seems to be that all pages were spidered much more quickly so the resulting drop was pretty fast.
Google and Yahoo are taking their time and some pages have been changed over in the SERP's while others have not.

**The site is a Miva Merchant site. The shopping cart and all functionality are module driven and I had the choice several years ago to shorten the dynamic (non search engine friendly) url's to "regular" url's by changing to the above method which is how the "c- and p- came to be.

Any thoughts on how long it may take to get the results back to where they were or even higher?

Thanks for your time!

[incrediblehelp]

Originally Posted by red

Each of the old pages have been redirected with 301's to the new pages.

As you probably know then, this is the reason fro the temporarily (hopefully) drops.