Just purchased the BL2 Season Pass and it worked. Tried to purchase Walking Dead (the game obv) and it no longer worked so it looks like it's a one-and-done code.
I'm getting the Crysis banner, but the specials list Dead Space -75% and Dead Space 2 -25% as well. Bet they'll fix it to be Crysis and everyone gets a spoiler for one of the next two days!