Via Panic Blog:

Defining roles is important What happens when you’re truly a “flat” organization and you have a bunch of incredibly smart people that can all offer valuable input on almost every task happening at any one time? Things can actually slow down a little at times. You want the right people on the right tasks, and you want someone who can make tough decisions and process the possibilities. It’s possible we’ve outgrown complete flatness. We’ll be experimenting with this more into the future, although it’s so tricky — you don’t want people feeling excluded, and you don’t want to extinguish the passion of creating!