After being open for five or six hours and used intermittently, Firefox 5.0 locked up on me and it took the usual many attempts to close it,”Program not respondng” and several attempts in Windows Task Manager.
Some improvements, but that part isn’t corrected.
I’ve been using it for about the same amount of time. I’ve added a few add-ons, and have used it continuously. No problems. I can’t say FR is much (if any) faster, but Firefox does seem to boot faster. I haven’t had to reboot my PC during this time, so I can’t say a fresh Firefox boot will be any faster.