Well if they're going to reveal it somewhere, E3 is the place to do it! But I just got my Wii U, so unless I win SuperHuman, I don't see myself getting an NX.There are a ton of rumors, but I don't think anything will be officially announced until E3 (that's some time in June). Most people are speculating that it'll be released in late 2016; maybe November-ish.
I just lost on purpose in Smash Bros, and my brother was watching. He couldn't tell I did it intentionally.