Everything you currently need to know about this is in the link.
But to give my own two cents, this makes me very happy. Rareware is a company with a sad history. They gave the world some of the best platform games on the N64 (DK64 and Banjo Kazooie and Tooie >>> Super Mario 64, there I said it) but then their most talented members left one by one and Microsoft bought them, which resulted in a Banjo game which removed everything we loved about the first two games and a bunch of shovelware Kinect titles.
But now, this game is in the works; it's Inafune and Mighty no.9 all over again!
Plus, Grant Kirkhope is part of this project, so the OST has high chances of being phenomenal.
Honestly, unless this turns out to be a Xbone exclusive, I hardly see any reason not get hyped.
Avi credit to Bathroom64