I just uploaded the latest 2.0 Beta (Beta 9) and updated the auto update information.
The main new thing is the new support for the just released Private Messaging API of App.net. This includes the retrieval, the display in your Views as well as the sending and the conversation view for the PMs. As far as I know Nymphicus is the first Windows client featuring PMs and one of the first in general. I have to say once again that the APIs of App.net are great – same for the documentation.
Also Beta 9 has some Stream Marker optimizations next to some more user interface improvements – both are still work in progress so.