Here is the February 2009 webmaster report on Google's search result changes based on the WebmasterWorld thread. I will summarize what people are noticing in the Google search results, as per the thread.
- Google accidently labeled the internet as malware
- Some SEOs noticed index counts double in size
- Some are reporting a "glitch" that promotes .edu & .gov as Google Bombs
- Longer tail keywords seem to be 'rollercoastering' in the SERPs
- Tedster's theory is that Google is tweaking the QDF (query deserves freshness) and QDD (query deserves diversity) algorithms.
That is the bulk of what I pulled out from the thread.
Forum discussion at WebmasterWorld.