I wouldn't say 'worried', as it matters little in my life if Nintendo succeeds or not with Wii U.
Your points reflect my own thoughts.
I love the Wii and will continue to play it for years to come. It is still the only console I can play games like LoZ:SS, Godfather and Bully with motion controls. Tiger Woods is probably better on PS3 now with Move but Move has little else to offer me. Neither does Wii U - and that is a fundemental problem.
Nintendo sold the world on motion/immersion and now appears to be abandoning it (as the main focus) to ape Apple. I think this will put MS in the dominate position next gen with a much improved Kinect that will allow you to experience games in a way no one has before without the limitations that 360's kinect has. That may not turn out to be the case, but at this early juncture, I think Nintendo will have a major problem building hype for Wii U and much more keeping it once 720/PS4 come out or Apple's rumoured game system does.







