The heavily camouflaged crossover you're looking at is latest member of GM's Theta family. Designed to replace the Pontiac Torrent in the Buick-GMC-Pontiac distribution channel (and possibly the body-on-frame GMC Envoy), the GMC Terrain is expected to arrive in the middle of 2009 as a 2010.
A number of GMC-specific design cues separate the Terrain from its Theta brethren (Chevrolet Equinox, Saturn Vue), including blocky wheel arches, a stubbier truck-like front end, and a nearly-flat roof rather than one that slopes in the rear as is becoming commonplace in the segment.
Best guess for powertrain options at this point would be a version of GM's 3.6-liter V-6 that's been making its way into multiple vehicles in the automaker's lineup, mated to a six-speed automatic.
Additionally, the North American Terrain will bear little relation to the Middle Eastern model of the same name, although it is a Theta-based vehicle. The Middle Eastern Terrain is a rebadged version of the Opel Antara/Saturn Vue.