Mine was a thin, regular sized envelope. I almost started crying before I opened it because I *knew* it had to be a rejection letter because it was so thin. The first sentence of the letter thanked me for my interest in the program, so I *knew* it had to be a rejection letter.
But the second sentence said I was accepted.

They had me fill out the bottom half of the letter to accept my spot and THEN they mailed me the health packet, etc. a few months later.
So it could be either. So don't cry before you open it!!