Yup. There's a microblogging app (Twitter clone) called TentStatus, available hosted at https://tent.is, or run your own instance of the code: https://github.com/tent/tent-status. Several people are working on iOS and Android apps to support the microblogging use case.
Meanwhile, the inventors of Tent have 5 people working 60+ hours a week running Tent.is and developing the protocol and apps for it. They haven't revealed what's next, though it sounds like some non-status apps are in the works.
Not off the top of my head, no. Sorry. :( I know there's http://tent.is, and there's a Go client for Tent out there, but that's really all I know about it.
Going back to P2P: building a flooding P2P library on top of a DHT seems like a total waste. But maybe the common parts could be extracted.