I think I have 1200 or so left from way back when I played Halo Reach, I guess I grew out of Halo because I didn't even bother to get the premium map packs. Now what I'm really hoping for is if I can USB mod for Skyrim, you don't have to jtag only thing you are modding is the saved files. In Oblivion with a couple of nice programs you could mod all numbered stats, health, encumberance. Change enchantments on weapons and if you went a step further and learned alittle Hexedit you can make your own custom houses, and races. For instance my Skingrad house had portals to wizard's tower, sky castle and my own Oblivion realm.
I don't see any reason it won't be possible to do it again.