I’d certainly like to see a return of the UX of Usenet, nothing that came after equaled its effectiveness. Unfortunately, that UX is difficult to translate to mobile devices, because it basically requires to be keyboard-driven.
There are GUI NNTP clients that could be adapted to work on a mobile platform. Thinking of webmail clients, you could do something very similar in terms of article selection, replying, new message, etc. The only think that would need to be accounted for is posting replies incline and with proper text wrapping.