It seems like there was a major update over at Microsoft Live Search. The update appears to have begun some time yesterday morning.
The update was suppose to loosen up the spam filter a bit to allow the crawler to index more sites and include those sites in the search results. Maybe Microsoft tweaked that filter just a bit too much.
According to a WebmasterWorld thread, many are complaining that the search results seem to be full of poor quality sites. Here are some of the responses at WebmasterWorld:
MSN has done another update and they now have HORRIBLE results. It's ALMOST as bad as Yahoo's now and that's bad!
Even WebmasterWorld's Live Search moderator, caveman, commented:
Don't often comment in update threads anymore, but am forced to agree. Oddly, both authoritative sites (often with ranking pages that should not have ranked), and quality niche sites, seem to have taken a hit on this go around. I expect it had something to do with ridding their SERP's of the dominance of stray pages from high auth sites (i.e., where the stray pages were ranking too well), but the net result has been more pages from iffy, third tier sites ranking than I have seen in long while.A lot of spammy mini-nets too. Reminds me of Yahoo five years ago. Especially the weird stuff, like niche sites with top ranking homepages, and badly performing high level subpages. Illogical, split personality stuff.
He adds that he believes Microsoft's geo-targeting and local-detection algorithms seem off as well.
The update before this one might have been on February 6, 2008, but Microsoft rarely confirms an update has taken place, so we typically don't get official confirmation.
Forum discussion at WebmasterWorld.