This question intrigued me because I had never heard of what you are talking about. I did some searching around and didn't come up with anything resembling power, third-row folding seats. I checked with our friends at Truck Trend and Motor Trend as well as Truckin and Mini Truckin and the editors at those publications haven't heard of this either.
I think it sounds like a great idea but it looks like there isn't any indication that Chevy will be manufacturing such a thing soon.
I hope this helps!