According to a recent report from Search Engine Roundtable which said that Yahoo Search is undergoing an algorithmic update, following noticeable fluctuations in search positions observed by a thread at WebmasterWorld.
The last revamp by Yahoo Search occurred in early September.
This is interesting, because we normally do not have a Yahoo Search update until the first week of the month. Conversely, the thread at WebmasterWorld is pretty convincing, in terms of this being a real update.
There is also a DigitalPoint Forums thread discussing a spike in traffic from one webmaster. Hopefully, you all might have seen a spike in your traffic as well!
Other forums discussing Yahoo Search update are: WebmasterWorld & DigitalPoint Forums.
Also, over the weekend there were reports of a Google Toolbar PageRank update. In fact, Matt Cutts of Google basically confirmed the update before it happened, saying:
I would not be surprised if new PageRanks started showing up this weekend or so.
News of the update comes on the heels of weekend reports that Google also updated its PageRank feature, which determines a website’s perceived value on a scale of 0-10. (The higher you are on the scale, the more likely you are to appear prominently on words relevant to your website.)
That being said, here are the forums discussing the update:
Sphinn
DigitalPoint Forums
Webmaster World
DigitalPoint Forums
This toolbar PageRank update does not seem to be accompanied by any actual search update at Google, which is now normally the case. And a random check across a few Google Data centers reveals it has propagated everywhere.
Recent comScore figures found Google served 63 percent of US-based searches in August (an increase of 1.1 from July), followed by Yahoo with 19.6 percent (a -0.9 decrease from July, when it enjoyed 20.5 percent of US searches).