WebmasterWorld moderator, martinibuster, posted a thread at WebmasterWorld documenting a pattern he is seeing recently with Google. He is asking, not telling, if people agree or disagree with his theory. In short, he is noticing that Google is apparently ranking sites that have their keywords in their URL/domain better then Google has in the recent past.
One of my sites with the keyword in the domain (no hyphens) jumped up to number one and started making unprecedented amounts of money. I checked it's backlinks and referrals and DMOZ/Yahoo but no change. The only change was Google giving my site a boost because, and I can't explain this any other way, because of the keyword in the domain. I've not done any promotion to that site at all. Zero.
I've also been seeing an unusual amount of parked domains that are exact matches for the keyword sitting at the top, although they seem to have been dialed back today.
Like with most of these threads, some agree and some disagree.
I have seen some cases of this being correct and some cases of this not being correct.
Of course, there must be some other factors that are hard for these webmasters to isolate. So the discussion continues...
Forum discussion at WebmasterWorld.