I have friends who go to Burning Man just about every year, but I've never been there. They tell me that some years are better than others as far as the overall vibe is concerned. A few of them say the festival is actually getting a little more corporate, even though the organizers try very hard to keep commercial interests away from the event.
I also thought the festival organizers were more ambivalent towards the use of recreational, albeit illegal, drugs. The way it was described to me, there are different sections of the festival grounds where different things are tolerated. Some areas condone nudity, while others allow responsible drug usage or consensual sexual activity. There's an internal "police" force, as such, but they aren't required to report misdemeanor crimes, like drug possession.