Interesting. The $2.5M that mcone mentioned was venture from Andreeson Horowitz, not subscription revenue. Also, according to CrunchBase [1], their parent company has raised $7M total. I wonder if this announcement means that the parent company is shutting down, or the employees of that company are no longer working on App.net in a full-time capacity.
[1] http://www.crunchbase.com/organization/mixed-media-labs