I'm not so sure about the linux port... it's more than likely code for hlds (half life dedicated server) which they put out for linux (but no linux hl2 client as far as I know)
*shrug* It's real alright, valve spokespersons have confirmed that.
It's the whole engine, but no artwork, etc... i.e. you can't compile it and play HL2... but game designers can learn about the AI and physics engines (there by nullifying any competitive advantage valve had in developing this advance gaming engine in the first place)
It also seems to be of boon to cheater coder, hax coders, and serial gen folks =P (although i imagine that code will get redone)
*Shrug* on another note... anyone playing CS 1.6 via STEAM?
Add me to your friends list (my username is surprisingly rampy or [DI]rampy) I'd love to glock, AK, or usp a fellow byoacer in game =P
rampy