Star Wars: The Old Republic opens up today. If you pre-ordered the game through a traditional retailer or virtually through Origin, you'll be able to hop into the game today; assuming you're lucky enough to be a part of one of the waves of entrants BioWare is letting in, periodically, until the game's official December 20 launch.
The game can't allow everyone in all at once, probably because it would crush the servers like the windpipe of a Death Star insubordinate. Persistence should win you your prize, though. Well, persistence, and a pre-order code, and a monthly subscription.