Bakemonogatari. Owns all.
Uh, if you want something a little more mainstream though, Darker Than Black's pretty good. Ouran Koukou Host Club is girly, but if you can get over that it's very funny too. Ditto Lucky Star, although it's not girly in the same way (and in fact is directed at guys in Japan). Sengoku Basara is ridiculously over-the-top and very easy to get lost in if you don't know your feudal Japanese history (hint: play Samurai Warriors), but it's also a masterpiece in my view.
And oh yeah, throw my vote in too for some of the old classics like Bleach. They have their weaknesses but for the most part they are popular for good reason.
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Signature credited to Nathan (or whatever he decides to call himself next)MSN address: yamiken (at) hotmail (dot) co (dot) uk
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