Totally unaltered Fedora 14 install from LiveCD in a virtual machine and the forkbomb did nothing whatsoever... just prints:
bash: fork: retry: Resource temporarily unavailable
forever in the terminal. This does not slowdown the system or create an drain on cpu and as a result had no impact on the host either.
I wonder of Fedora 14 is made to somehow limit the number processes.
Phenom II x4 B55 BE Win7/Fedora 14 dual boot
Compaq CQ62-220US Vista Ultimate/Fedora 13 dual boot
Acer Aspire One D250 Ubuntu 10.04