I love GM-less games. Seriously. After decades of having to be the area "weird GM" because no one else ever wanted to run new and experimental things, the rise of GM-less RPGs hit my sweet spot when it came to finally getting to play. Whether it be Remember Tomorrow or Umlaut, games which transfer narrative control to the group as a whole rather than a singular figure are making my life better.
Something that's not, however, is trying to shake loose the folks who've been limited to single-source narrative control in traditional GM/Player relationships. Some games are better than others for that (Umlaut being one of the easier ones, since the defined "moves" at any given turn are limited), but I wonder if others in the community might not have some suggestions or techniques to help get the more trad gamers into the dynamic a little more comfortably.