Well, I do a pretty fair ammount of ripping, encoding, and burning (mp3, ogg, divx, etc)and I generally keep my cpu monitor up during that process (so that I can see any spikes-- they generally create skips.) I haven't had any spikes that weren't releated to an external cause (generally me slacking off and not shutting down my mail and im programs and it deciding to check mail and someone iming me at the same time.) I haven't seen one since I got my chip over a year ago. I did occasionally get them under windows 98, but I've not had any under xp. Which leads me to believe that either it wasn't directly related to being a P4 or it was some other problem (irq?) related to the motherboard. Shrug, basically its a non-issue now as far as I know and have heard from anyone.
Shadus