Before your post, I didn't think of checking. Holy cow! 100MB of RAM!
My Sony desktop has 2GB of RAM installed, a 65-nm Intel dual core 3.2GHz processor, and I just installed the new Western Digital VelociRaptor HD (10,000rpm, 16MB cache, 3 gigabits/sec transfer rate).
So Firefox v.3 doesn't affect performance with this hardware, but I suspect it may adversely affect performance with older machines.
I cannot compare the RAM usage with prior versions, because I never thought to check. All this said, I stand by my suggestion to the Pirate that you test it and compare overall performance to IE.
Captain Billy and I are alike in our conservative dispositions. I keep my old Jeeps running, and have absolutely [b]no[/b] intention of replacing them. They're paid for, cheap to insure, and go everywhere.
But you don't have to give up anything by trying the new Firefox v. 3 - just park it on the hard drive and open it when you wish. It won't launch on its own, so you have nothing to lose.
Rick/Portland, OR