When I was at the Louvre in '04 I had the distinctly surreal experience of being the only person I could see looking at the Mona Lisa -- literally everyone else within my field of view was taking pictures as traffic gradually pressed them from one side of the room to the other

I'm sure some percentage of the people were, and I just don't remember them, seven years later...

But I agree that the painting itself is not any more impressive 'in person.' I found Da Vinci's Madonna of the Rocks absolutely stunning in person, however.