Well, one person's progress is... I still never use any modes other than aperture priority, shutter priority, and full manual. I never use any program modes.
In other words, it gives you a way to replicate shutter priority and aperture priority. You just make the adjustment via exposure compensation rather than shutter speed or aperture. Whatever works for people is dandy, but I never saw any advantage for me to fuss with it.Most detractors of the Programmed Automatic system decried it because they assumed that the photographer needed to accept whatever the camera selected as the final exposure. In fact, with Programmed Automatic you are offered the entire spectrum of shutter speeds or f/stops to select from. You can then adjust the exposure up and down using + and - exposure compensation.
The one new feature I do use--although as infrequently as I can--is auto ISO. There are some situations where it is indispensable. In fact, one of my only complaints about my Canon bodies is that they don't allow EC with auto ISO. However, when it is practical to do so, I would rather control ISO and keep it as low as I can.