No, absolutely not only Christians allowed! I commented because earlier in the thread there were lots of general posts along the lines of how stupid it is to believe in this shit. That isn't what Op was asking though. There has been a really good discussion about how much historical evidence there is/could ever be for the existence of a minor prophet called Jesus who stirred up trouble in a small region around the year 20AD.
Whether said prophet actually was 'the son of God', whether God exists and intervenes in the world, and whether people who believe that will believe anything, is a different conversation.
Also the digging about in the traditional nativity story, where it came from, what actually happened historically- it is an interesting conversation for some people regardless of their faith. There are lots of little historical details which add to the story- there was a spectacular comet around that time. That doesn't mean that God sent it to guide philosophers to the cradle of a baby boy. It's still interesting though.
And if you want to write it off as a load of nonsense not worth thinking about, that's absolutely your right. Why hang around here though, where people who do find it interesting are having a chat? It's like going into a bar when a big football match is on and complaining loudly that it's not as good as rugby.
Oops, long post, sorry. Must have used up all my patience earlier...