d0nni3 on 16 May 2011
Yea i activated mine, just linked through the PS3 then clicked add new game on steam and entered my code.
If you didn't have a steam account before you should have set one up through portal 2 steam overlay then you may have to activate the account through e-mail i'm not to sure then it's the same meathod when your logged in, if your still struggling get in touch with steam support there not the quickest people on the planet but they should get you all sorted out
