Bleach.
I would have said Naruto a while back, after all it appealed to most audiences and I loved the drama and emotion that drove the plot. There was some really moving arcs. . .
Manga Spoilers: however when you start to resurect every single character from the entire series as a
zombie than I think - as they say - that you've jumped the shark :P Not the mention the very repetitive 'don't go, Sasuke!' followed by Sasuke attacking, leaving, then meeting up again several chapters later to repeat the process of 'don't go, Sasuke!'. Oh, and the whole moon-hypnotism thing is sooooo Dr Evil too
End Spoilers
Bleach, however, does have its faults, but at the moment it's still going strong. It has great plots, fantastic and diverse characters, and excellent artwork, and it's generally pleasurable to watch. I'm still watching Bleach, I think I stopped Naruto the moment Shippuden began, and only read the manga to see if it's possible to outdo itself in terms of cheesiness.