I can attest to the fact that you are more quiet and shy in person, BUT then again that was only the first time I've met you, and a lot of people are shy when they first meet someone.
For me, I'd say there's not too much of a difference really, although I'm sure there are some small ones. But I'm generally quite chatty and get on with people. I dunno, people from here who have met me can probably give a better answer!