My daughter started 1st grade at age 5 years and a few days. The school tested her, and it was a no-brainer to do the skip from their perspective. They gave her extra acceleration in a couple subjects immediately.
They made the decision after she spent a couple days in school last May. The visit was a wonderful experience for her because it gave her a precise idea of what to expect from school. From that point onward, she was very excited about school. There was no anxiety at all. So, put me down as agreeing with Austin's suggestion to let her spend some time in the first grade class.
It was clear that she wouldn't have got anything at all out of kindergarten. She's been very happy and has actually been learning stuff.
Val