If there is a chance that you may relocate to another area at any time during the next twenty years, consider the fact that your child may be the youngest in his class. Consider what that means during adolesence and teenage years. Peer pressure is always present during those times.
If you do choose to enroll your child in kindergarten, be sure it is developmentally appropriate. It should not have an academic emphasis but rather an abundance of activities such as singing, moving, sharing, listening to stories, learning rhymes and playing. Kindergarten is the foundation for all future learning and where the love of learning begins.
A trip to the local school and visit with the principal would be very reassuring. The principal can give you the philosophy of the school and kindergarten in particular as well as the number of children in the class who were born between September and December of the year your child was born.