That's kind of how I feel for most big series (that I enjoy anyways) set in a different world. There's always so much to them, I just want to learn more about that setting xD
It's how I felt about Eragon (I think it would be awesome to learn more about the other continents, new heroes, new villains) and it's how I felt about Codex Alera (there was just so much history in Alera they could have touched upon, all the extinct races, etc.)
Well, that and I just don't like not being able to read it anymore xD