I'm not sure what is going on, but after installing an update a few months back, you've been sucking pretty hard. There's two main issues you're having.
The first is that you've just been stupid slow sometimes. You'll frequently freeze up for 30 seconds when I load a page. Can't change tabs. Can't stop the loading. Just frozen. Generally, you comes back, but on occasion it's just gone until I Ctrl + Alt + Del the legs out from under you and start over.
The second is that you frequently just completely crash. I'm in the middle of doing something and *poof*. The window is just gone. I restart and get your, "Whoops! This is embarrassing" message and then you reloads everything I had going. At least you're cool enough to remember what was going on. But this is happening daily. WTF is going on Firefox?
I know I've got a dozen tabs open of articles I'm reading, perhaps some streaming internet radio and then Skype, Acrobat, and some other heavy RAM munching programs out there, but my computer's beefy. It can handle. You can handle.
I love the Firefox, but I've already downloaded Chrome. It's a little too minimalistic, but I swear.... I'll use it if you make me. Play nice.