Windows in plan 9 are images that are drawn to. There are libraries for drawing fonts and various shapes.
Another thing that get conflated with text interfaces is keyboard control. For whatever reason the plan 9 developers were very adverse to this and preferred mouse based interaction.
Anyway plan 9 is interesting because of how it's different. If you're approaching it asking "Where's emacs and vim?" or "Why can't I get my shell history by pressing up?" you're probably not getting the full value out of it. Part of the problem is probably that it's close enough to unix to make people put unix expectations on it.
Here's a video about acme, a programmer's interface for plan 9.
Thanks for the long reply, though I must admit I'm aware of all that. I was hoping for some surprise information.
Your comment of it seeming like Unix might be the key point to take away. I know that I'm supposed to search in the buffer for history and use the mouse to select and rerun it, but having tried it multiple times, I cannot get comfortable with a mutable terminal buffer. That's also why in Emacs I only use term and not the editable terminals. Maybe one day I'll get comfortable.
Curses has nothing to do with the unix philosophy, and "terminal application" should not be confused with what is actually characteristic of unix: its IPC and IO model, and its possibilities for composing programmes through those. The fact that you most often utilise these features through a terminal emulator that runs a shell does not mean that curses and the ilk are essential to unix because they happen to draw interfaces in those terminal emulators. Curses it not more or less unixy than any other windowing/UI-widget library.
I don't understand what you're replying to. I didn't say curses==unix. Most terminal based applications use curses, therefore the lack of it limits the pool of applications.
For what it's worth, anything that does more than just print to stdout breaks in 9term.