All, Please take a look at this thread: http://forums.mydigitallife.net/threads/12742-Explorer.exe-Crashing-In-Windows-7-x64/page4 It is...
It looks like it's been fixed, although I'm not sure which version of FF will integrate it first (or if 3.5 embeds it already):...
Please take a look at this: http://support.mozilla.com/en-US/forum/1/481957
Sorry, I forgot to mention I am using W7 x64 Ultimate too. But it looks like the same happens with Vista x64.
I had the issue with Windows 7 x64 (7600.16385). I found out in another forum that indeed this is due to a Firefox 3.5 bug. And the issues...