My DD12 is in eighth grade and is with her social peers. She will graduate from high school and start college at 16 and the idea that she wouldn't continue with these same peers into college is something she says she would never consider. These are her friends and, with guidance from us as necessary (although, at this point it still hasn't become necessary since we've run into no age-based issues thus far), I am confident that she will continue to do well as a part of this same social group. Our plan is to continue to have thoughtful conversations with her about all kinds of growing-up issues and then just trust (as all parents do) that she is equipped to deal with things that come her way, with our support.
On another note, I was never grade accelerated, mostly because I had a twin who wouldn't have done well with it, and all my best friends throughout high school were at least two years older than me. I did hate that my friends and I were separated in grade-based activities when these people were my true peers, and it was lonely when all my friends graduated and went to college before me when I knew that I was just as ready as they were.
So, any decision you make can go any way, and so much depends on the individual. I agree with the other posters, though, that while it is good to consider the ramifications of a skip, for now you just need to follow the needs of your child. And remember, almost any decision can be reversed if necessary.
