>the gains seem like they will be minimal

The article and published study quantify the gains:

>The suit weighs about 11 pounds. The team's research, published Thursday in the journal Science, finds that a person wearing this suit expended 9.3% less energy walking and 4% less energy running, compared with wearing no suit.

>That's the equivalent of shedding 16 pounds of weight while walking or 12 pounds while running.

I wouldn't call these "minimal".

Yes, I saw the stats and still think "minimal" is exactly correct. If you read my link, the unpowered version showed an 8% metabolic rate reduction while running. If you put batteries and motors on something, I would expect the gains to be quite a bit better than that for it to be practical.

Idle thought: Is a bicycle an unpowered exoskeleton? What if you clip in to it?

Do you ride on it, or does it ride on you? Is an exoskeleton a vehicle?

Car is more of an exoskeleton in that regard. When you put on the seatbelt, you're wearing the car.