Apparently the authentication server was down (and who knows what else). It said I didn't have CS installed. I flipped Steam the bird and said "Screw you, Steam". Steam smirked and grabbed it's vapor crotch. "Ooo, Steam, that really burns me" I replied. So I uninstalled Steam. Steam was pissed and all, but you know how it goes. Pretty soon Steam'll be all up ons.
On the (semi) upside, there's a 700 mb (ack) download that includes steam and all the full batch of cache schtuff for the different games available.