I would humbly suggest you eschew emotion in the proposed email as much as possible, and limit the email to the topic of holiday visitation (the middle 3 sentences).
If the only communication he receives from you is by such simplistic emails, he might be more inclined to use email. Or not. Unfortunately, we can't change other people.
The more cold, dispassionate, and direct at this point, perhaps the better. If he is angry that you are not being more emotional, that's his problem. He has probably done plenty to get himself into the position that he is in.
If he has any questions, he will let you know - you need not ask for it. He doesn't sound like the shy type.
Okay, I'll delete that email and try again.
Is this better?
Please confine discussions with me about visitation via email as per court order.
In regards to your inquiry regarding holiday visitation:
The court orders give you visitation the first Saturday of every month. Your next visit with the child is January 3rd, 2009. If you have any questions, please let me know.
(Last bit cribbed straight from Wiley's suggestion.)
The shortened version you've here is much better than your initial attempt, which sounded almost whiny. Which I can understand - if your ex were a more pleasant person, he wouldn't now be your ex. But writing and deleting (or burning) is much better for you - and saves having to pull your hair out.
Remember: no matter what you send, there is a 99% chance that it will be misinterpreted.