I have tried Google's TC Malloc, and now I'm getting interested in FreeBSD's jemalloc.
I'm writing this blog post from the Firefox 3 beta 4 linux distro, and its very nice! Can't wait until iceweasel 3 is out in backports. Its not in sid yet so I'm not holding my breath.
Regarding memory allocators, this is a good read:
I had to disable the OCSP SSL certificate validation for whatever reason.