That trailer was for version 3.0, and was made before the release, while 3.0 was still in beta, and the features that you're talking about apparently didn't make the cut, as they were never in an official release that I know of.
I'm sure someone could write a script to implement the graphical icons showing joint state.
As for the bar at the bottom, I'm guessing that the icons would be to pause a replay [p], resume playback [p while paused], advance one frame [Shift+p], and restart replay [r]. I'm guessing that it wouldn't be too hard to implement either, but there's already hotkeys on the keyboard for it, albeit slightly undocumented ones.