although this has obvious potential for construction and other tasks, i doubt we'll ever see a weaponized version.
1. cost - price isn't described at all in the article, but you know it's astronomical.
2. protection - you could armor this thing until it couldn't move, and it will still be defeated by cheap and plentiful weapons in use today.
3. purpose - are you going to put a cannon on it? dumb. room-to-room fighting? no way. as long as there's a person moving his legs back and forth, top speed and mobility will be a lot less than a horse, much less a jeep. the only effective role (ignoring cost) i can think of is riot control.
any thread about powered exoskeletons would be worthless without mentioning the palladium sci-fi/fantasy/horror/whatever rpg "rifts". where else can you battle cthulu with 50 foot tall robots?
http://www.palladiumbooks.com/
http://en.wikipedia.org/wiki/Glitter_Boy