There are a lot of MOV (QuickTime) files on Gnutella which do exactly what their WMA/WMV equivalents do i.e., redirecting you to a website. Furthermore, Mac OS contains no magic whatsoever, if there are few viruses or even none, it's only because the small marketshare of Apple isn't worth the effort. That said, I'm pretty sure a lot of people are grinding their blades currently and as soon as the Intel-Mac is widespread, there will be a big gore feast. I mean, they really deserve to be punished for not skipping x86 in favour of the much more secure AMD64 platform at the very least.