And all this time I was hoping the sequel wouldn't feature the Joker at all...
First of all, I don't really like the character that much. Second, I thought that the end of Batman Begins was too much of a setup for a sequel with the Joker, and so I didn't think it would actually happen. And third, I was harboring a secret hope that the sequel would have Dr. Crane in it; he was my favorite character in the first.
Oh well. Batman Begins was the best Batman movie I have ever seen, so the sequel will likely be good, Joker or not.