I really liked death note. The story line was good, but took a bit of a downward slope at a certain point. I'm a fan of monologue, suspense, story plot tiwsts, and psychological battles.
I didn't really like the series as much when they introduced the new characters. If you're into strategic and psychological battles, well that's definately what you're gonnna get. Heck, even fans of the mystery genre can fun with it.