if you do a lot of video work, stay with apple. final cut studio is just such great value you can't match it on the peecee side.
talking about value, i think quite a few people here have missed a good point, including you, mactruck!
yes, you can buy a maxed out XP system for $2k, or the equivalent mac for $5k, but think about how long each will last before you end up upgrading them...
i've got a dual 2.5Ghz PMG5 and i've never had to upgrade it. it's now got FCS 5.1 on it, Adobe CS2, Aperture, all the latest software still runs as well as when it was new. i'm not going to have to upgrade that beast for another 3 years, at the earliest. if i'd got a peecee, i'd have upgraded it within six months. that's what i was used to before this G5 came into my life - buy, upgrade, upgrade, buy, upgrade... etc. i never had a peecee (including "top of the line") that i had more than 4 months before i had to start pouring money into it.
just look very carefully at maintenance and upgrade costs - work out a TCO for both, the mac'll come out cheaper.
and then, if you're still unconvinced, look at adware/spyware/viruses and compare them there. there's one thing i couldn't stand on my video system and that was running all this extra, power-sapping, crap, just to keep it all clean.
i could never move back to a Windows based machine. it was just so much hassle. and FCS really is the dog's balls.