I've been on the site for a good week now (@kristian) and there's some incredible people there. Great conversation, great progress on determining just what this project is. That's not a bad thing — the nature of a project like this is that it is evolving constantly.
In that vein, I encourage people to check out an issue filed at the App.net API page on Github.
https://github.com/appdotnet/api-spec/issues/33
The basic idea is a reworking of the API into something more extensible. If I'm understanding correctly (I'm pretty new at this stuff), the API at this point resembles the use case of something like Twitter: users have many posts, posts have text, a date, etc (Rails associations, anyone?). This issue proposes that the access control on those posts be variable, to fit an infinite amount of use cases. A couple examples are Twitter-style DMs (posts visible between two users), mailing lists (posts visible between specific, but multiple users), etc.
I think the thing that is causing App.net problems is that people think they are funding a Twitter clone. The fact is that the basic system of "users" with "things" goes a lot further than Twitter. It's email, it's chat, it's notifications, it's whatever you want it to be. And that's what's fascinating — we're funding an extensible piece of the next phase of the Internet — something decentralized and more or less living and breathing.
So here comes the part where I tell you to fund it. But I'm not going to. It's your call. I'm a huge fan of the service already and I can tell you that within the last two days, we've had a mobile web app, native iOS app, and streaming web app pop up out of nowhere. It's a crazy active community, and now's the time to get in. If you want to fund it, you probably know by now where to do that. There's my 2 cents (though arguably that was like 80 cents).