Rumors are all over the place based on a NY Post article and Slashdot publicizing that article. Basically, the logic that Google is really making a browser is that Google purchased the domain name Gbrowser.com, based on the whois record you can see they purchased the name on 2004-Apr-26, pretty good logic here.
Anyway, forum coverage at: Cre8asite Forums
And here is my lame attempt to turn the Mac IE browser into a Mac Google browser: