Well.. just shut the book after finishing it. The non-Adams sequel to the Adams universe.
I'm... a bit torn about it. To be honest I love these characters so much that being with them again felt so good I instantly took a liking to the book. The tone certainly helped, it was very, but not quite, entirely adams-y. It gave me a few chuckles and, I think I'm counting right, three out right full-on out loud laughs. Way lower a humor average than the Adams books, but still pretty good.
The story itself, though... that wasn't very Adams-y, I found. Adams was certainly random in his humor, but there was a logic to the randomness. A cleverness that Colfer doesn't quite dominate. Poignancy. When Adams interrupted the story's flow to describe some hilarious random universe happenstance it wasn't just hilarious, it usually also offered an insight. Adams always made me think, and that's something I always loved about him. Colfer got the tone right, and certainly was successful dressing up the writing in an Adams-y way, but the CONTENT was way lighter. Dumber. Not as great.
I'm glad I read it, but I don't know if it earned its place next to my Ultimate Hitchhiker's Guide to the Galaxy omnibus hardcover. Maybe next to some other less-important books, though.