A lot of rankings are dropping, and one webmaster even reports that he's hit a new traffic low in 2008.
One member likens these drops to the fact that Google might want to emphasize their paid listings.
Looks to me that at this stage of the game where Google completely dominates the market it would be beneficial for them to have "inconsistent"/"moving" results in the natural search so people would click on the ads as those are consistent. When searchers will get the idea that they will not get the same (even though still relevant) result every time they search, they will most certainly pay more attention to the ads. Google getting richer?
That's definitely an interesting statement.
Other observations include blogs being ranked higher, link exchange websites taking a hit in the rankings, issues with relevant rankings (specifically, more relevant internal pages are now being replaced by the less-relevant home pages for search phrases), and a lot of dropped rankings.
Forum discussion continues at WebmasterWorld.