I've been reading around trying to get a scope of the rumor mill in the immidiate run-up to E3.
I haven't seen anything concrete, but I have seen Star Fox mentioned in the press and in the blogosphere a whole lot more than I have in a long time. I probably haven't seen this much pre-E3 Star Fox speculation since the run-up to E3 2006, which was a month prior to the release of Star Fox Command (Star Fox 64 3D kind of came out of nowhere at E3 2010).
That said, it isn't specific. It is worth noting that back in 2006 we knew SFC was coming, having been announced at GDC in 2005. What we have now is a general rumbling that a Star Fox game is going to be announced for the Wii U.
The question is this: Do these people know something or are we seeing an echo-chamber effect here where enough people are speculating that everyone is picking up on it. I guess we'll find out in about 23 hours from the time of this posting.
I'm trying not to read too much into this, as that can lead to disappointment easilly, but the number of people running with it is intriguing.