I do not believe they play heavily into the decisions process, but obviously they are considered.
For those of you who aren't satisfied with your SAT scores, try taking the ACT as well. I never took the SAT, but my PSAT scores predicted I'd get something like a 1340 for the combined math and CR score. I took the ACT with everyone else at my school and got a 34. When I talked to the ROTC instructor at Stanford, he informed me that the school translated this into a 1520. Much better than a 1340 in my book.