I've been a big fan of adventure games since 1982, when I played the text-based adventure Dungeon on a DEC-10. I thought The Book of Unwritten Tales was just great. I loved the humour and the references to Tolkien, Terry Pratchett, Star Wars, Indiana Jones, etc. etc. All in all, one of the best adventure games I've played. The puzzles were challenging, without being frustrating.
Currently FPS games dominate the market, and the lack of humour in them is very depressing. The only recent games I recall that have some humour are Serious Sam, Duke Nukem Forever (that unfortunately grossed people out with its over-the-top sexist jokes) and Half-Life 2 (a few very mild jokes). Adventure games seem to be the last refuge of humorous narrative in games.