The Calgary Flames are red hot. Momentum is the word being tossed around a lot right now, and it's pretty applicable given that the Stars appear to have none and the Flames are more or less overflowing with it. The Flames haven't lost yet this month; the Stars' power play has scored only two goals in the Present Age.
It's worth nothing that the Stars' power play plummet has them ranked at 4th overall in the NHL, still. That's evidence of just how fabulous (and unsustainable) it was early on. It may also be evidence that this team has been thoroughly scouted by the other 29 at this point, so it's time they adjusted.