The way how Applications interact with users are going to change dramatically dare I say.
Notifications are out, so it could be a challenge for new apps to get more noticed. Publishing to stream is now a two stage process instead of a one. I hope the user has patients!!
On the plus side though is that real email addresses are being made available, and friends can try and entice the friends to use the App from an inbox message.
At the Hackathon I got to meet other Developers and Graphic Designers, and learned about frameworks such as Ruby on Rails
and Code Igniter
which help to speed up the developing time of making Facebook Applications.
My contribution at the Hackathon was integrating the Dodgeball Flash game into Facebook, by providing scripts to Invite Friends that are interested in Doritos or Dodgeball, and providing scripts to send notifications to friends, and produce status updates and wall posts. Im glad to say that I was part of the winning team that won £1000 for taking part in the challenge.