I wasn't aware they were producing a DLC right away.
Xbox users (and maybe PS3 users as well, not sure) are used to most games having nearly immediate DLC availability. The stuff that comes out immediately is usually just cosmetic stuff, like special gear, or maybe an extra map or something. But for this game, it seems like a better idea to get the thing working properly before releasing DLC/Expansions.
As someone who plays Skyrim on PC, I find all the clamoring for DLC amusing. Mainly because DLC isn't as common for PC games (except ones that are also released on consoles), and usually modders are able to put out decent expansions (albeit with nonexistent or crappy voice acting).