i personally wouldn't be surprised if the delay is caused by nintendo.
considering the leaked trailer with NFC features, the announcement of AC figurines releasing this summer (dissimilar to the one in the trailer but the design could've been revised), ubisoft ceo yves guillemot's comment about how nintendo "[...] will make the necessary changes to the machine to make sure that it continues to grow fast on the market" and the fact that an nfc update is coming to the wii u later this year..
wouldn't it make sense if it's all about timing/marketing? why release a game now when (possible) key features won't be available until later this year? perhaps nintendo will reveal similar nfc features (eg figurines à la skylanders) for the new 3d mario, pokemon x/y or (*drool*) super smash bros! i can understand people's frustration with the current software drought, but i'm cautiously optimistic regarding the reason for the delay. and really looking forward to e3! :D
Essay Pro