Seahawks' defense did a great job against the Rams. As others have pointed out, the Seahawks had a big advantage over the Rams in total yards, time of possession and first downs. That is very encouraging.
Against the Seahawks' defense, Stafford wasn't the MVP-caliber QB that everyone was talking about. He was 15-28 for 130 yards.
On a slightly related topic, how terrible is it that the Falcons traded next year's first round pick to the Rams, and it's looking like a top-10, and possibly top-5 pick, given how badly Atlanta has been playing?