I think the issue isn't whether your son is gifted, but more "how gifted is he?" Have you read up on designated levels of giftedness? There's the traditional MG, HG, EG, PG and then there are "Ruf Estimates" which go from level one to level five. See hoagie's gifted for more detailed information on these.
If he's already multiple years ahead across the board before even setting foot in school, I agree with Trinity that homeschooling might be a good choice. If he does have some 2e stuff going on, home is clearly a place where he can get around his challenges and learn.
Two of my own kids started out in school, and after we brought them both home to learn, we never even considered trying school for the younger kids. If Davidson Academy landed in our backyard, we'd probably enroll, but short of that, few schools will be able to individualize as well.
good luck!
