Well Naruto came down to last page vs plot holes.
I forget to mention these 6 zetsus hiding, and orochi took Kabuto's memories, and there was a counter for the reaper death seal, and oh ya, there was a secret Uzumaki shrine in Konoha. Does all of that outweigh OMFG ALL THE HOKAGES ARE BACK!!!!!!!!!!!!! At this point the plot doesn't matter to me anymore. It's all about the bad ass fights and summoning them has "potental bad ass fights" written all over. Although I am still a bit upset the unsealable reaper death seal is unsealed by a mask and cutting the demon's belly then killing yourself. Then Orochimaru just switches bodies and everything is ok.
Bleach could be wrapped up in one sentence. Unohana is killing Kenpachi over and over again so she can unlock bad ass Kenpachi because he was a bad ass little kid who put restraints on himself so he can enjoy his fights. At this point I'm like, don't try to understand it, just go with it. It's Bleach.
One Piece was plot development, and some bad ass plot development too. Law telling the flamingo to resign as a warlord was bad ass, but I really doubt he will.
Idk, this was almost a tie between OP and Naruto. Without the inconsistencies in Naruto, it would of been a land slide. I know, I'll say Naruto but vote for One Piece. XD