Now that we've gotten the title over with, here's something for the Windows geek that could be a lot of fun.
I've been using Quartz Composer, and here's how complex the McCain-pissing-Palin image is:
Plug the image into the particle thingie. Plug the other image into a sprite. Make another sprite black for background. It's stupidly easy.
VVVV looks a little clunkier to me, but it's the same concept: plug this unit into that one and you have video. It also looks quite a bit more powerful than Quartz Composer, and it's likelier to have many more people adding freebies to it.