Yes! I was actually planning to start another character soonish when I've got the free time, or get started on a few of the sidequests that I haven't bothered with yet (e.g. Dark Brotherhood) on my main character (lev. 48 Khajiit with ~200 hours on it). I haven't had time to play much for the last few months, nor to even have had a look at Dawnguard yet. : (
Is it any good, by the way? I don't really know anything about it beyond what I picked up before it was released - I know that it's got (more) vampire and werewolf stuff, but beyond that - not much. How long did it take you folks to finish the main quest?