Didn't expect it to demo, but I do hope they use the time and money they save not doing one to groom and debug Skyrim. It's rare I get this excited about a game, and I know that they have a disappointing history of buggy releases and patchwork apologies are infrequent. I've always played their games a few years out of the gate (timing, systems don't mesh up, whatever things get delayed) and whatever bugs they had at that point were 'to stay' but there weren't as many as you see people talking about just after the release. Being that I am getting this one fresh... I want it to be groomed properly first.
So, keep the demo, but do a good job on the testing phases of the game and get those bugs!