Check out this story from Johnnie Moore's thought-provoking post, Change Management and Mistaking Green for Gold:
A few years back, a well-known consultancy business decided to abandon it's dress convention of dark suits and white shirts and said folks could dress casual. But quite soon, they decided to make it a bit clearer just what counted as casual and what was unacceptably scruffy. They thought they'd changed, cos people were no longer wearing the boring suits. But just below the surface, they remained a company fixated on telling people how to dress.
When you think about bringing new ideas to your next conference, keep this story in mind. It's more common than you'd think (because, of course, it's more comfortable to change the surface than the infrastructure, in so many ways).