As many have already said, this can only be seen as great news. I was dreading the thought of them spending 20 minutes on this title during E3, considering I've already played the first one and I'd rather just be mostly surprised upon release. It also means that they have enough stuff to show during E3 that they don't even need 2-5 minutes of time from this title to pad their presentation.
The best thing, though, is that there wasn't the slightest hint of a leak for this Direct. It hits tomorrow so we don't even have time to build it up to overhyped proportions. Good job, Nintendo. Your internal teams are holding your secrets well and hopefully that track record continues into E3.