Treecritter, I second the use of the IAS. It was very helpful even to the admin. as they were not aware of it's use and having never accelerating a child, it made them feel at ease with their answer to move forward.
Catalana, if it's any consolation, I wouldn't be fearful of not accelerating based on the basis of a large friend pool. My DC is one of the extremely outgoing gifties (I know many are introverted) and she left so many friends behind and we went ahead with the full grde skip and she has adjusted beautifully! In fact, she didn't adjust at all! She has made just as many friends in the new grade and you would never know that she wasn't with this kids from kindergarten! If your child makes friends that easily, he will be so well adjusted even with leaving the others behind. In fact, if nothing else, we have even more friends now because we have the friends we left behind and all of the new ones we made! It was a win win for all!
