I must have missed the memo where Firefox was already properly multi-core ready, with add-ons and jetpack actually growing thus making this browser relevant again.
I hate Chrome's evil, but I hate suckiness more than I hate evil. So Chrome it is for me.
This is the most fundamental truth. I hate Chrome for all the tracking it does on me and my browsing habits, but I just can't switch. I almost made the switch to IE(!), but session restore was buggy. I tried to switch back to Firefox, but everything is slow, even scrolling is choppy. Not much, not everyone notices it, but it is there. All the super awesome extensions I used are useless. Features missing, version not supported etc etc. And the UI. OMG the UI. It's a throwback to XP. Tabs made of cheap glossy plastic, 4x3 grid menu in which last row has only one icon. I mean, are they even trying?
IMHO, they should scratch the code. Start with Chromium, so their process problem is solved, and implement a powerful extension framework. That is what defined Firefox, and that is where their success lies.