MySpace runs Windows?
Jesus, 4,500+ servers running Windows 200x server? What did that cost for the software licensing alone? Let's see, where I work our "Microsoft Volume License" cost for Server 2008 standard is $256.25 per server. So 4,500 licenses at that price is: $1,153,125.00 (at retail: ~$4.6 million).
Even if they got it for half of the volume rate, which I doubt, that's still a sizable chunk of change. I'm no Linux advocate but it seems to me that for considerably less than $1.1+ million dollars they could have hired some capable Linux admins to maintain their systems...