This looks way different compared to the older Stargate SG-1 and Stargate Atlantis series.
The plot revolves around a group getting stranded on a spaceship with a stargate on it. The ship is on an unstoppable course heading out of the galaxy, and the stargate connects with planets it comes near. So the crew can explore the planets but has a limited amount of time to get back onboard ship before it gets too far and they are stranded on the planet.
Also, via AICN here is the [youtube]http://www.youtube.com/watch?v=fl5AOJatwYg[/youtube].