It really doesn't matter who you are playing as in the past 4 games: you always have shields and you always have health (though it isn't always visible and it regenerates in two of them). They are obviously aiming for something a bit different with Reach. Unless they make it a more tactical game, they won't accomplish that by simply saying "hurr, ur a SIII nao!" and then putting the same damn mechanics in again.

In their defence, their mechanics are perfectly fine, and the game does look like it will be fun irregardless of whether or not they keep it the same as the previous games. I'm just a bit disappointed that so far they have chucked the books out the window; hell, I wouldn't even call it a nod to them, I'd call it a steamroller.