We've seen Halo 4 in action, people, and it is gooood. Our own Jake Gaskill was on hand with the developers at 343 to check out Master Chief's return and write an excellent Halo 4 preview for your reading pleasure. Here is a small taste of Jake's eyes-on preview of Halo 4.
"Halo 4 isn’t just 'another Halo game.' At least, as far as its intention is concerned. 343 is building Halo 4 to be the foundation on which the next decade’s worth of Halo will be built."