GM's recent TV advertisement shows the driver engaging their version of autopilot and crossing his hands...I was like woah! That would never make it through legal if they weren't very very confident about their tech. Contrast that image with Tesla's demand that drivers keep their hands on the wheel and it seems that GM is miles ahead of everyone on autopilot.
From what I've read, GM is less confident about their system's ability to operate under as wide a variety of situations as Tesla's does. Yes, it operates in a hands-free manner, but does so only on well mapped uninterrupted divided highways, and even then it requires the driver pay attention. It does this by way of the IR lights and camera mounted in the steering wheel, which only allow the driver to look away from the road for a few seconds at a time.
Given the bad press that Tesla gets after any Autopilot driven accident, GM seems to have made a safe choice here.
GM's AV systems are leap-years ahead of Tesla's. Pretty much everyone in the AV world is, including Uber (the recent accident notwithstanding). However, GM is taking the safe and conservative approach: restrict the usage of a feature that could potentially kill its users to a specific set of situations in which extraordinary testing has demonstrated that it won't. And that's exactly the right way to do it until they get to true self-driving.
