Some of my favorite bits were Carter's random comments about the weird goings on in Percy-land (though he has no idea what they are.)
Rick did a good job once again with the balance of humor and serious stuff. There was a lot of times where I was hanging on every word waiting to see what happened next and right when things seemed to be getting too intense he'd throw in something like Sadie convincing the hunting goddess that she'd had unspeakable encounters with Jelly Babies.
All in all, I really enjoyed the Kane Chronicles. Percy Jackson will always be number one in my book when it comes to Rick Riordan, but I'd definitely read more Kane Chronicles-related stories if he were to write them.