I have to agree as there are times where I would have a shit ton of tabs open at the same time and thanks to a meter, I would see about almost a gig of memory being used by Firefox. At first I was "woah wtf?", but then as soon as I killed it, the mem went back to nominal levels.
I do enjoy setting up all related materials up on tabs and well... I can't feel all that comfy with my resources being hogged to a browser, if only incredibly better than IE...