That's because you haven't gone here and installed the userscript. I left that link to prevent this sort of thing. Please read the entire post before commenting. thanks for the bump
I have: Mafia II, Sniper Ghost Warrior GOLD (gifts) and Magicka and Alan Wake American Nightmare (keys) Also have cards, and can get TF2 Keys, i already added you :)
Selling a full set of 10 Mystery Cards for 5 keys
Check out my inv to confirm IDs
Info on Mystery cards and their IDs can be found here