My buddy is a buyer for the forces, and he was at a trade show last year. Saw a user wearing a powered exoskeleton, carrying 600 lbs and jogging on the spot.
It's my belief that a few hundred pounds of kevlar, dual-wielded jackhammers and a diesel engine (not unlike Big Dog) is only a logical step away.
I give it ten years until powered armour is a feasable reality.
The main point, as has already been made, is whether or not we'd actually ever find a feasable use for them, which is... unlikely.
Death Watch Killteams in areas of heavy insurgency would work pretty well though
IMO.
But, as my buddy said - suits of awesome would cost literally
millions apiece. You can buy an RPG7 for about $200 in Afghan. Do the math