Those of you who have already had children probably remember the first time your baby had a good belly laugh. What did you feel like in the weeks before? And how did you feel after? I'm willing to guess that you were more relaxed because your baby let you know that you were as funny as you thought you were. I'm also guessing that in the days following your baby's belly got pruny with mouth farts because you were trying to re-create that laugh.
So new dads take heart! Unless you have a voice like Ben Stein your baby in all likelyhood does find you funny. That first laugh should materialize in 12 to 16 weeks (according to this article) and you will finally have something in common with movie stars.