I think the social part of grade skips is really underemphasized in these discussions. The puberty issue is something to think about. So many posters here just brush that off. What will it be like to be the only kid not driving? Or not going through puberty/dating until college when everyone else is doing that in high school? Etc.
That is not to say your son will have a problem, but just to point out this aspect of grade skipping.
Both of my kids are super bright, and are super small (5th percentile). We are small parents so it's likely they will be short as adults too. We have chosen not to grade skip them due to this physical and social aspect- to us, so much of being a "boy" is how fast you can run and jump, the macho aspect, etc.
There are downsides to not grade skipping- both of my kids are 2 grade levels ahead and are sometimes bored. However, they aren't so bored that they are suicidal or depressed. Both have lots of friends and are in a very good place socially. We aren't sure if that would be the same if they grade-skipped.
