As a developer, I'm a lot more excited about it. I backed mainly because I was so excited about an API that could've been what Twitter promised. I'm especially excited to see what annotations is going to emerge through it. To explain it in short: Any app can now embed any information in a post. This is big. To give a small example: Say people who allow IFTTT to post their music to app.net. IFTTT can decided to add meta information to it (adding song titles, artists, etc). Now anyone else can easily extract this information.
There is a whole underlying network waiting to be discovered. Anything can now live within in it. What if you wanted to do an instagram type app? Ask users with app.net accounts to log in. When they post a photo, add your own information to it (photo title, photo url, etc).
In the normal app.net (alpha) interface, you won't miss anything. You'll just see someone posting a photo. However, now this new instagram type app can extract this information from a user's feed, using app.net's infrastructure as their social backbone! Any social service can live on app.net's infrastructure now.