My opinion to Halo 4:
I'm going to buy the game just because I've really enjoyed the previous games, but with the loss of our beloved Bungie, Halo could be taking a massive risk.
This will be their first Halo game (I realize I'm Cpt. State-the-obvious), but that's not what scares me the most.
I'm most fearful of how they're going to change the game (Classes, Armor abilities, Armor customization, etc...).
I'm afraid that they'll see what CoD is doing and attempt to make Halo more like CoD, mostly because CoD's a top-seller.
Either ways there's nothing I can do to change how they make the game (I hope it ends up being good, I'm sure we all do).
Also there will be no beta (cOLD, I'm aware) this could be a huge risk on the franchise, since we can't tell 343I what should be added, removed or changed.