We know nothing about Halo: Reach other than the fact it's a new Halo game, and that it's due sometime next year. So in the absence of facts, then, let's speculate!
While the game's trailer lets us know the obvious things - it'll deal with the Covenant's attack on the human colony of Reach - the end of that trailer, and the game's first artwork, hint at a little more.
See, the colony of Reach was, before it fell to an attack from the series' alien villains, a training ground for Spartan units. One of the game's first spin-off novels, "The Fall of Reach", tells us this.
So we know it's crawling with Spartans. Enough Spartans that, in the game's debut trailer, we hear at the very end a radio message saying "you've got Spartans on the ground, sir. We're not going anywhere".
Spartans being plural. Many Spartans. Spartans speaking as part of a team. But how many? Looks like at least five, going by the game's first piece of art, which shows off a motley collection of Spartans including a sniper, a "heavy" and what looks like a female trooper second-from-left.
So will Halo: Reach be a squad-based Halo title, starring not a single Spartan, but a team of them? Recruits, maybe, or at the very least a TF2-like assembly of characters with varying weapons and skillsets?
Who knows. We don't. That's why we're just speculating.