I really hated the whole Walt/Anubis thing. And every chapter that Sadie narrated she constantly talked about them, it was annoying. I did really love Carter and Zia's mall date, though.
I love Rick Riordan a lot. I have all his YA books except the little side ones he does for series, and i'm getting Mark of Athena pre-ordered. He's my favorite author (next to Helen Keleher, but y'all wouldn't know her....)