User blog comment:HaLo2FrEeEk/Full Dawnguard playthrough coming Tuesday!/@comment-82.38.231.18-20120625230631/@comment-4111310-20120626053121

I think there is really only one dragon that is seen in the DLC (wouldn't know not a beta tester) but other than having to kill dragons for the first time, it won't have a huge effect.