The Android's Dream, by John Scalzi
Yay! It's a John Scalzi book!
There were a number of spots in this one (especially in the first half) that had me laughing out loud, even when I was at work around other people. Before I read this I saw all kinds of refrences to the book starting with a chapter long fart joke. And it does, and I laughed. Because clearly inside my 28-year-old female body there is a 12-year-old boy, or at least his sense of humor. (and when did I become 28? what is up with that?!?)
The basic idea is that these aliens need a specific species of sheep for a coronation ceremony or else they'll have major political upheaval on their hands. (It's an "Electric Blue" sheep, hence the book's title) There's also some major players that are a not so thinly veiled poke at $cientology which personally I found quite hilarious.
There's some very very cool AI stuff that I liked a lot. When he first showed up it was the first "gasp, awwww!" moment in the book for me. Someone needs to get on making that whole concept a reality.
There is a lot of humor and it's a very different writing style that most of what I read (I think I said about one of Scalzi's other books, OMW maybe?), but there's also a lot of relationships and connections and people that you can root for.