Well it hasn't got messy yet but there is still time ...
I had a look and read the text - the illustration was funny, and the knowledge that a church had put it up even funnier (I always thought Joseph had drawn the short straw in the nativity fable).

There is a serious side to it though which really represents a major breakthrough is dismantling some of the nonsense which makes christianity so hard to accept i.e. the virgin birth. That particular church seems to be saying ok we know this can't have happened but the essential core of our religion is 'love'.
Progress? Or is the concept of 'universal love' nonsense too? A discussion perhaps not for here.

PS:
I like this
http://www.chavtivity.com/

Jimit,
I find it funny. I think it's good if we can all, as humans, laugh at ourselves, whatever that may be - our religious beliefs, or even the traditional belief from the French that the British can't cook.
Told without venom, I believe any joke can be funny, if it is taken in the context of the true meaning of the word "joke". If we could all get a better sense of humour maybe the World would be a better place. We're becoming offended too easily these days.
Regards, and best wishes for the Christmas holidays, whatever religion you are,
TE.