Actually, Nvidia owns the patent thing as far as I know because when they bought out 3dFX a few years back, they inherited the patents also (back then 3dFX had dual video cards also).
But I won't be getting dual video cards unless Ati gets off their ass and decides to support it also even though not as many people will have it but its a nice thing to know.
But PCI-E and AMD =

for me