If Firefox hadn't gone on a version roller coasters ride I'd still be using it. At least they pull versions that need more attention. But, FF 16!?!?! 16!!!? Huh?
. . . you do know Chrome's at version 22 and version 24 is in dev release, right?
Knock FF for the more disruptive update process, and for breaking plugins in earlier releases, sure. But (AFAIK) the plugin interfaces have been stable for quite some time now, and Firefox 15 introduced true silent updates. They seem to have fixed the pain points in their rapid release schedule.
If you use Chrome, however, you cannot knock them for iterating more quickly; Chrome's in the same boat.