I was of the belief that babies smiles are not expressions of emotion until their 2nd or 3rd month.
"Smiles while awake are reflexive reactions to a face or voice rather than an emotional response. However, during the second month, your baby's smiles are a genuine sign of pleasure or friendliness. "
It may not be wind, but it isn't an interactive smile which is what i was getting at - I am looking forward to the point in time where there is genuine interaction.