Personally, I thought the game was... good. Not excellent but certainly far above average.
I've never read any of the books but I don't think that Fone Bone is a really good character. Phoney Bone on the other hand is quite probably one of my favourite characters ever now. There's something compelling about watching him stump about and being a complete and utter bastard is a new Adventure game character type which I really quite like.
The graphics are very nice, except for the actual normal looking people. Simple, yet very nicely done.
The mini-games are mostly okay. Although I'm none too pleased about the running thing. The second time I had to do it my computer suddenly decided to minimize the game and spend forever to do nothing in particular. Then the game didn't maximize again and i hadn't saved for about an hour. I suppose this wasn't really anything to do with the actual game though.
Overall I think it's a pretty good game, yet it doesn't give me that special tingly feeling I get inside whenever I play a really good game.