I say yes. One of the principle elements I wanted to tackle in this game was the idea that players often end up in a very reactive relationship with the GM, who's often at one end of the table, and everyone is always waiting in a sort of Pavlovian way for them to explain how the world reacts to the player having just rolled dice. This puts a lot of pressure on one person, and can all too easily fall apart when players take actions or make decisions that the GM didn't think of on their lunch break the afternoon before the game.
Rather than pin the world and the plot to one person, I wanted everyone to have an opportunity to contribute at that creative level. To do that, the typical GM functions got split into player actions and Director actions, all designed to affect story and plot inertia by prompting decisions. By giving everyone a chance to be that Director with narrative control, and so long as everyone continues to work together for collective "we're-here-to-have-a-good-time" benefit, then the burden is off one person at the table to make sure the game "doesn't suck tonight."
So yes, I see shared GMing, as GMless, because the responsibilities still exist, they're just now in the hands of all the players.