Mac is my main. I have a XP at home, and I know how to use PC, but I don't really care for them as they seem to have more problems. The biggest downside to Mac is the amount of Windows exclusive software in the market.
video editing software: iMovie<WMM<iMovie HD
iMovie HD came with my first college MacBook. Transferred it when I got my MacBook Pro. Not a bad program for making YouTube Poops; has more effects than WMM, but it's no Sony Vegas or Final Cut.