I'm about as interested in DMing as I am in playing. I love seeing players do unconventional things. My latest DM interest is to run a long term, gridless, RP-heavy game. My latest player interest is to make a character that will be chronicled in some way, whether by integration into a running setting or getting a spell or item named after him/her.
As a DM, I can be a little authoritarian in my approach. I won't railroad, but by the gods if you actively try to subvert the party's goals, the hammer will come down.
As a player, I defer to the DM most of the time. My concern is not only fun for the group, but for the DM as well, and I do my best to see what the DM wants out of a game. That said, if I'm promised an "exploration campaign" and get a dungeon crawl again, I won't be a nice person.
I believe fun is fun, and that it is everyone's job at the table to make sure everyone else is having fun too.