Kinda scratching my head. It's definitely a well done site and app. Problem is, there is no problem here. I'm not going to ship you a package to your @twittername address. The few times a year I send someone something via mail, I'm going to want it to be over and done with. I don't want to have to wait for you to respond to a tweet (which 90% of the people I know don't regularly use or ever will).