The Inheritance cycle. I strongly STRONGLY recommend the eragon books. If you've seen the movie, don't even think for a second that the books are as terrible as the movie was. The only trouble I have with the book is pronunciation, but I'm a perfectionist. I can't rest until I've correctly pronounced words;]
Eragon, Eldest, Brisingr, etc.
Also, I'm sort of enjoying the Percy Jackson books, they're alright. Then there's Artemus Fowl, Rapture...
Oh, and if you like the Twilight series, I suggest "The Host" by Stephanie Meyer.
These books are a few that one who enjoys those that you have listed, might also enjoy. If you are brave, I also suggest you look into Dean Koontz, Dan Brown, etc.
OHOH! And Keys to the Kingdom, those were GREAT books!