Tried a Fedora Core 3 64bit version on my AMd64. There were a lot ot crashes and freezes!!!!
Hope Fedora Core 4 makes a better appearance. .Tried a ubuntu Kubunto version 5.05 Hoary Hedgehog.
There were no hitches.
Common to all is that a "Mocramedia Flashplayer" for 64 bit environment at the moment is not!!!!!!!! available.