And try to tell me the version doesn't matter when there's a regression or otherwise something broken on a newer rev that works fine on an older one.
I don't know where this recent trend of "version numbers are evil" came from, but it's entirely silly.
On the dev side, you might refer to a particular code snapshot with a "version number" that might as well be 3.2 or r304 or "2011-08-3 12:03:47" or d1b119d8f117b16fcfa58b2be60df87a6c45ac58. Considering the nightmares caused by conservative IT groups enforcing version X of software Y for years, eliminating version numbers from the public for something as critical as a browser seems like a good move to me on security alone. For other things the formal major.minor.release-revision can still make sense. Personally I miss the "even minor version represents stable, odd unstable" pattern that's increasingly fallen out of use.
Web apps and installed programs are completely different animals.