Have you read the Fall of Reach -  novel? In the novel it depicts that all of the spartan teams bar one were deployed down onto the planet's surface, one team was send to retrieve something (Won't spoil it for you) but it had John in it - Master Chief, hence his appearance later on, but apparently everyone else on the planet have been lost - after all the planet was "glassed" shortly afterwards. Not sure if JUN had managed to escape or not - but apparently all ground teams perished.

all you have seen is a trailer filled with CGI and random shit that wont even happen in the game and your already saying it will be the GOTY. what a moron

The best bit of the interview was actually this...

We had to maintain that commitment to the sandbox nature of Halo gameplay - making sure we're empowering players to make choices in how they approach each problem instead of giving them only one solution. That was one of the things we held at the core of everything we did." So far, so familiar.

Those new sandbox battles will be deliberately like the ones fought in Halo, rather than the similar-yet-somehow-different firefights from Reach. "Halo's original campaign was kinda under-designed," says O'Connor. He means it as a compliment:

"You learn the sandbox at your own pace, and I kinda miss that. It's something I would like to see come back to the Halo universe. I sometimes feel that modern games are overdesigned - they funnel you into fights when really what you want to do is smell the roses. Halo used to let you do that. As it got more modern, it tended towards more defined encounters and experiences. Reach tries, I think successfully, to make you use all the elements of that sandbox in a very certain, rigorous, action-packed fashion."

The bolded part is music to my ears...