Memberships usually do not sell out so you may wait to register at the convention. In fact, this year the line was so incredibly long for preregistration that it might even be faster to wait (although next year may see a switch as all those who were in the prereg. line figure this out). I will say that the badges for preregistration are larger and possibly valuable (to those who collect them). On the other hand, hosting hotels sell out very quickly. If you want to book a room in a Dragon*Con block, you should sign up as soon as they open. If you do not get one in a block, you can try to reserve a room anyway. I advise that you do not tell them you are attending the convention since some hotels will not allow you to book a room if they know you are attending the convention. Yes, this actually happened to me. If you belong to an organization like AAA, you can try to get a discount that way, or just ask what specials they have running. Once in a while I get a rate that is better than the convention rate (this may involve paying ahead). You should ask about refund policies before booking.
Fun Facts: (from the Media Relations Handbook) approximate number of attendees 35,000; volunteers 1,700; guests 400; years 24; hotels 5; days 4.
Read more »