I have to say that I love the teasers for The Social Network. This is the second teaser, and it is still a true teaser, not showing any scenes from the movie. The genius part of this trailer is that they used the Facebook format for communication (walls, messages, etc.). You do get to see images of the characters via their Facebook profile pictures.
The Social Network is based on the rise of the Facebook phenomenon. David Fincher directs the film with Jesse Eisenberg playing Mark Zuckerberg, the founder of Facebook. Justin Timberlake, Andrew Garfield (the new Spiderman), Rashida Jones, and Max Minghella also star. The Social Network is in theatres October 1, 2010.