Apart from the fact that it's extremely early days for App.net right now, this article assumes that Twitter will remain as it is now, and not deteriorate further with significantly increased levels of advertising and spam. App.net will likely become increasingly attractive as Twitter becomes more "manipulated" to deliver on those promised eyeballs.

I've paid up for App.net because I have a zero tolerance policy to advertising, and I don't want to be involved with services that have their primary business model built around marketing and advertising. In this case App.net is not aping Twitter, because Twitter will never indulge the idea of a world without advertising.