The awesome bar is actually pretty awesome. Initially I didn't care for it in terms of it's auto completion side of things. However when it came to finding an article that I knew I'd read 6-7 days ago but couldn't find the URL for, the awesome bar made it incredibly easy to track it down. Having a full text index of sites you recently visited is a handy thing indeed.
I leave browsers running for weeks. My Windows boxes are so reliable that I reboot them once every 60 days on average – aren't yours? Anyway, what's the point of that sort of stability if you have to do things like shut down your browser? Well, Firefox 3 seems to have some sort of weird pause and glitch mode when it's left running over a long period of time.
What's weird is that the glitch seems to occur after 5-10 minutes (sometimes more) after starting to use the machine. All seems fine for a bit, and then Firefox decides it needs to do some incredibly urgent maintenance which couldn't be done during the previous 6 hours while the CPU was at 99.99% idle. Weird. I'm hoping other people spot this and it gets fixed, as it's incredibly annoying.