FWD or AWD?
Either way, the 3.6 doesn't have a TON of torque right off idle, so it would take an extreme lead foot to wear out tires that fast. My old 2006 GTO with 425 HP and RWD didn't go through tires that fast.
It's possible that your toe is off. If the tread is still flat against the road (camber) but the tires are toed in or out excessively, you'd get excessive wear. However, this type of wear usually results in feathering, where the tread blocks show uneven wear when viewed from the side. It can be tough to notice looking straight at the tread.
I've only had good experiences with Michelin's, so please do keep us informed. Unlike every OE Good-for-a-year tire, which has eventually cupped, slipped a belt, developed radial pull, or vibrated... well before it wore out. I've never gotten my money's worth out of a set of Goodyears so I was glad to see GM using Michelin.