I have memory-hemorrhaging problems under various versions of Windows as well. I need to restart at least once a day (I typically have ~8 tabs in use).
But the clincher that made me switch to Chrome a couple weeks ago was that every couple of hours it would decide of its own accord to tear off a tab into a new window, and then hang. This solved the memory leakage, but not in a useful way.
I'm pretty sure that my problems are related to badly-behaving addins. But Firefox doesn't provide any good way to troubleshoot addins (compare to Chrome), and it seemed to me that the process to track down the culprit given that the problem is nondeterministic and takes a couple of hours to manifest would be more difficult than the switch to Chrome.
That said, I'm having some compatibility problems with Chrome. Like, last night the CAPTCHA in the free annual credit report site wouldn't work.
Yeah. I had the same problem with chrome as well. Same setup. Maybe web browsers can't handle how I work with them at the moment. Maybe I'll go down the rabbit hole and try to fix some of the bugs myself.
I had 40 tabs open for the better part of last week and didn't notice a performance hit; and I've only got 2Gb RAM.