You might want to take a deeper look into the kindergarten program itself and the population of kids coming into it. Our kindergarten class had many readers and kids that had attended very academic preschools. It was designed to be open ended for kids at all levels. We actually had a pretty darn good K experience with a HG kid, considering there were 24 kids in the class and 14 were boys (we had a male teacher, so I think that weighting was intentional).
On the other hand, 1st was horrible. It was almost less academic and hands on. And it was certainly not as open ended for kids in many places. It may have served us well to do kindergarten and then push for a skip (we are now homeschooling).
I also know our district will not consider a K skip or early entry unless the child is reading very well. My son was just like this pre-K. Would not read - zero interest. Was doing 2-3rd grade math conceptually, lots of science knowldege. Very intense personality, but we didn't know we were dealing with a GT kid. We actually thought he was behind because he would not read. I think he tends to be more visual spatial (although, he was also a very active preschooler too. Sitting down with academics was not his thing). Jumped about 5 grade levels reading in a matter of months. So watch for that as well.
