Well, the tablet makes a big difference to me. It's a defining feature on the console and if/when I buy one it'll largely be because of the fact it will offer me experiences and software I can't get on other platforms. As a father to three young kids, asynchronous stuff and Off-TV play are killer features. The Nintendo IP and possibility of "family-friendly" software on the platform are also two big positives. Only thing stopping me from jumping in is the price and the software. Drop the former, fill out the library of the latter and I'll buy one.
Clearly I personally am more interested in the PS4, 360 2, Vita and PC stuff, but I think dropping the tablet on the Wii-U would be a big mistake. Why dump your distinguishing feature and sell, essentially, a 360 with a Nintendo logo on the front? With some decent marketing, targeting people like me, I can't see any reason they can't shift a fair few of them over the coming years.