@Kuro_San: I didn't know what Lain was until a couple of months ago.
lol DBZ is not overrated... It has created a new genre of anime that's why it's famous...
Overrated: Dragon Ball Z, Elfen Lied, Code Gease, Naruto, Bleach, One Piece, Hetalia.
I'm not sure if it's popular enough to be considered overrated, but Gundam Seed was ridicoulously boring and the lamest Mecha anime I've seen yet.
Underrated: Claymore, Full Metal Panic, Nadia: Secrets of Blue Water
@indifferentmrh: That's what makes it overrated. We don't need boring, takes 5 episodes of screaming and powering up to make a good anime, yet now most people think so.
Underrated, though it's only part anime, Oban Star-Racers.
Overrated, is Neon Genesis Evangelion. It's still good, but gets more attention than it deserves (probably because of the endings) and it can get boring sometimes with the same keyframe used for several minutes. MINUTES. Then previous works by Anno have been overshadowed by it (Nadia: Secrets of Blue Water & Gunbuster/Diebuster, both of which I have mentioned earlier).