> The advertising and constant "we updated!" tabs opening up (yeah, great, I don't give a shit, stop telling me) are at least as annoying as Opera's adbar was, IMO.

This was actually the last straw for me. I had 30 tabs open, and Firefox decided to take an update. Any time I opened a new tab, it demanded I restart my browser, closing everything, and refused to function. That level of interruption was so unacceptable I switched (back) to Chrome.