I've taken the stance that if God wanted us to know Jesus birthdate, He would have made sure we know it. It wasn't as important as why Jesus was here on earth. If His birthdate was in the bible, I thinks it's pretty practical to expect that people would grab onto the date and it would be made a bigger deal than what he did for us. Jesus came to earth in obedience to God, He came to glorify God. Perhaps if Jesus' birthday were in the Bible, we would be glorifying Jesus alone, apart from God. And we would feel obligated to make this ritual mandatory, or be limited by guilt if we didn't. I think that would be a very likely result.
My personal decision was to honor Christ this Christmas, just like I normally do. I went to Christmas service at church, but personally, I enjoy the regular services more, because they are about living life, and applying Christ's teachings to our daily routines, rather than having a birthday party, so to speak. I didn't decorate a tree or hang stockings. For me, this year, it just seemed like a distraction, like a sideways way to worship or celebrate, unnecessary and kind of like sharing my worship. It didn't feel right for me. However, I was invited to Christmas dinner at a household where they celebrated Christmas with all the decorations and gift-giving, and the tree, etc. I had alot of fun. I enjoyed my friends' company, I met Christians I haven't met before. I think it was a healthy place to be this Christmas.
Given the wisdom of God, I think there is a reason Jesus' birthday is not in the bible. We have the freedom to choose for ourselves, while making sure we do not let it become a bigger deal than why He was here.
Just my newbie understanding of the topic, at this point in time.