I've seen these alleged XT group pedals on several web sites, but they aren't on Shimano's site. The "PD-T780 Deore XT Pedal" is sold at Arts Cyclery (http://www.artscyclery.com/), Amazon, and REI, but at none of my usual online bike retailers.
It's odd for an XT product -- it's a dual purpose flat/SPD pedal.
Was it an old product that's no longer sold? Could it be a counterfeit? (If so, weird that REI would sell it.)