The Army is hoping to have such systems available in the next couple of decades. Bulk and weight are so critical here that I tend to be skeptical of the idea to use exoskeletons for some time. Consider that even if the exoskeleton doesn't increase the soldier's bulk so much that they can't maneuver in cramped indoor environments, the weight may be a critical handicap. Not all structures may have floors that will be able to withstand the weight of an armored trooper--especially in 3rd world countries. Also if unarmored insurgents are fighting armored soldiers they might deliberately make their floors weak enough that an unarmored person could walk on them but armored troops would break through.

 

When they are deployed they will probably be lower limb and torso systems at first where the pack basically is hung on the exoskeleton. A heavy armor vest would probably also be mounted on this chassis. If further protection was needed the soldier could wear full arm gauntlets if that was necessary. It seems to me that mounting a fully enclosed armored helmet that moves with the head on a powered "neck" would be good for additional head protection.

 

The soldier's arms could be powered, or the weapon could be mounted on an articulated arm similar to the setup for the machineguns in Aliens. The mounting arm would have the advantage of being able to supply a data link to the gun which could put the gun's aimpoint on a HUD for the soldier.

 

What I forsee when the technology is first introduced is a few soldiers being armored heavy troops and the rest unarmored light troops. The heavy troops would have the advantage of armor but the disadvantage of less flexibility, and might not be able to enter some structures. They would probably operate the infantry heavy weapons which would allow them to carry a heavier weapon (maybe being able to pack a OCSW as an MG, for example) and more ammunition but again at the cost of less flexible mobility.Heavier armor would make them less vulnerable to enemy fire while they were providing their teams with suppressive fires.  It would also be a good solution for increasing the mobility of troops armed with mortars, ATMs or Stingers. It might be necessary to provide some form of protection against RPGs however. What seems like a good idea to me is a slat armor shield attached to the machinegun, and/or the articulated mounting arm. Such a shield would have to be articulated to allow the soldier to lie prone without it getting in the way.