Completely agreed. I'm still on Firefox 3.6.x because of all this rapid upgrade nonsense ever since 4.x. The Firefox developers turned their browser into a bloated, clumsy knockoff of Chrome. They burned the soul of their product - no wonder they've lost ground. I don't know what I'll switch to on my Mac/PC once 3.6.x becomes too old to be usable online, but it won't be a newer Firefox (though it certainly won't be Chrome, either). Maybe I'll VNC to OWB on my MorphOS machine...
I was a huge Firefox fan from 2004-2009, but after version 4 it just became bloated and the ridiculous version number climb in the last 12 months, the nags for updates, plugins failing, the whole thing just feels bloated and messy now. Chrome is much more streamlined.