Yakitate Japan, becase a shounen anime about baking the ultimate bread is too bloody awesome.
Inuyasha is runner up because it had its high and lows (especially Naraku disappearing 230924830948304 times instead of being obliterated) but it kept strong, and since we're coming into the final chapters of the manga I can't wait to see the second half of the story animated

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Bleach got weak after the Soul Society arc. It's basically Ichigo fights character x and y now.
Naruto got weak after Sasuke left and it went into filler arc, but the sequel Shippuden got Naruto back into its former glory and even exceeds it, the story in the manga currently kicks a lot of arse
