I think I was using a lot of plug-ins when I took that screeny, like noscript, flash, flashblock, addblock plus, xmark and auto pager.
now I moved to 7264 x64, and running Minefield 3.0.10 which is the 64-bit firefox project mozilla are working on , so far so good. just running noscript, xmark plug-ins atm. here is a screeny of process memory usage:
so it's seems to be taking 130 MB, thats with 5 tabs open at the same time..