It means you are either linking to a site that has a bad rep or a site that once helped you rank no longer can because it lost weight. And I don't mean co-op weight, I mean the invisible weight that the search engines put on your domain based on the support that you get from other sites. It's not something you did or didn't do, just something that can happen when you put ALL your eggs in the SAME basket!
My guess is some form of link exchange program that has been viewed as farming or illegal by Google. I would write Google. You may or may not get a response, but it is an idea. That is some pretty serious droppage, so my guess is that you prolly have some idea of what you have done... maybe some BH seo work? I am not accusing, just speculating. To see a drastic drop like that over a WEEK and that many keywords etc... some very shady seo work was done, if you ask me.
The only thing I did that would be considered shaddy is use the coop network, and now I have stopped using that.
The Co-op network is shady? If that were the case, there would be a lot more upset people on this board and in this thread. The only problem that I have seen with the Co-op is that ads from completely irrelevant sites show up on my site. That is the only thing I would fix. Other than that, I have heard a boat load more positive than negative about the Co-op network.
Sitetutor is probably correct, that it's a "bad neighborhood" you've linked into. Try going through and reviewing any sites you linked to in the weeks prior to your drop. I recently came across a forum thread about this that was an incredible read. I can't remember if it was on the Cre8asite boards or another one. Someone else brought up the same situation and at one point Googleguy jumped into the thread and specifically pointed out a shady group of sites that had been linked to. Apparently they were using invisible keyword stuffing techniques (which could be found through checking CSS settings). If I remember where I saw that thread I'll post it.
Looking at your site itself I see nothing shady. You are just like so many members here: signing up with co-op, following the rules and then neglecting other avenues that could make you strong.
I think I might have figured out the issue. A few weeks ago my site had significant downtime due to server load issues. I think google did its index at that time and couldn't find my site so it didn't index it. I think in 3 weeks, when they do the next index my site will be found again and I will slowly recieve my ranks back.
I didn' think so ... ATL email me thru my profile and I lead you in the right direction! ,Linkin Park and Jay-Z is the shit !
I researched this issue and it is very much possible. If my site is down the whole time they are updating indexes then they find no new pages, which would explain my previous indexes still showing like normal.
OK ATL, I have just found out the reason, took me some time and resources but now I know for sure. Google shows 6k+ BL's but running thru the right software it is only 347 that are benefitting you ... Anyways, I cannot discuss it here ... email me if you want, otherwise goodnight
ATL....if it was downtime that affected your serps, you'd find that your entire site had been removed from the index. This happened to a friend of mine due running out of disk space (thanks to evil comment spambots). He hadn't looked at his blog in over a month, and because it was dead Google just erased it completely from the index.
Ok, I guess it would depend on the if it happened at about the same time I guess. Still seems a bit unlikely. I mean your site could be up, but just "unreachable" at the time due to God only knows what kind of outward internet/network problem somewhere else. So there must be some kind of check and balance to avoid a false posistive type response. We had a site that has been up and indexed for years down for nearly 1 week due to some issues with a server. It was not a priority to get the site back up, so we let it go for a week. Never will do that again though as the lost revs from adsense we not realized until a few days later. Anyway, we did not get pulled from google as a result. I am still suspect of this as a cause. Anything is possible though.