We recently had an internal debate about whether the anti-hyphen bias extends to the rest of the url. We haven't tested it though. I'd be curious if anyone has ...
http://example.com/something-about-something ?
Matt Cutts actually recommends using hyphens in this case:
Our own debate was whether to hyphenate a two word phrase in the directory structure: /kitchensink/whatever/ vs /kitchen-sink/whatever/. So we had to do a similar debate as the domain hyphen analysis. Spam signal/Google treatment vs. User Convenience vs. Does it really matter.
The sheer number of people doing it makes me wonder if at some point they'll implement it, if they haven't already.