Well. As far as speakers go, my Klipsch ProMedia 4.2 setup sounds *incredible*. Does it beat a nice high-end stereo? Probably not. But man... seriously, you have to experience it to truly appreciate it. They sound better than I thought they could. When I look back, $300 for this setup was a bargain.
I still haven't bought the processors, but it's a spot of some concern for me. Two of my friends built systems after I wrote this up; they both went with dual Athlon XP's, and now one of them is having serious troubles. The system won't boot anymore. The MP's do have some added stuff to make them work better together in an SMP setup. Which doesn't mean you can't do the dual XP's - it just means that it probably won't work as well. I'm still researching.
As for the drives... IDE are getting much better and much faster. The low seek on SCSI does matter to me, but as I explained above, for some reason it's just not sitting right with me now. We'll wait and see how that plays out.