Well...how far ya want to take it? If you build the right system..hell, you could safely do 60+ tracks with plugins AND VSTi's!!! Plus roll video along with it!!
Right now a PIII 650 with 512MB ram does me around 45-50 tracks with barely any plugins..add a couple of waves plugins and the umph goes down!! I have a 34 track song with way too many plugins happening and it's peaked around 95% on my CPU useage meter..I could add a couple more tracks but thats' about it..then I would start to hear clicks and get stuttering in the program(not the audio but the machine itself)
I'm also doing Video capture with Adobe Premiere and exporting it out to AVI file..then bringing it into Nuendo for Audio recording..works great!!
With a Dual PIII 1Ghz and higher or a Dual AMD 1Ghz and higher you could do some amazing amount of work..especially with SCSI drives!!
One thing about the PC is that there is Wavelab..I dont think there is one Two track editor on the Mac that can compare to Wavelab..I've used Spark and Peak tons of times..but it's nothing compared to Wavelab....and I've seen plenty o Mac users say that as well!!
So you see...a PC "can" do what you need...it's the right configuration and the right tools in that config that make it work right and get the work done that you need it to!!
Opus

Okay...so say I have a system like this...
PIII-1000Mhz
Asus TUSL2-C
512 megs of PC133
ATI 32Meg Rage Pro Video
40gig ATA-100 7200rpm (OS) Hard Drive
60gig ATA-100 7200rpm (Record) Hard Drive
48x Cd-Rom
TDK 24x10x32 CDRW
56k Modem
Microsoft Internet Keyboard
Microsoft Intellimouse
Windows 2000
(I found this at dawbox.com, by the way, for $1239.99)...no mention of the sound card though,
what else would I need *(or not need) to start producing/recording some good stuff, say 30 or so tracks worth? *(I won't be using my system for internet access)

The P3 system I was looking at on
http://www.infinitevortex.com
comes with a Creamware PowerSampler sound card with the sound card's drivers installed and
the Luna2 installed with V3.01, PowerSampler(STS3000) and Elektra(Modular2)
plugins all activated. I really have no clue what these things are. Would this be a better bargain at $1768. considering the importance,or unimportance of these options?