I played D&D 3rd Edition my last couple years of college, and then moved on to variations of 3.5 Edition for a couple years. Had a couple friend who were really good DMs (what amounts to the storyteller/god of the game). My roommate was known for his harsh tactics and insane attention to detail. He spent an entire summer building a whole world, then ran probably 7 or 8 of us through it. It was crazy. Mine was the only character to live the whole way through.
Early this year, I decided that since I couldn't find anyone to play with, I would DM. So I bought the 4th Edition Core Rulebooks and "Keep on the Shadowfell", a premade adventure meant to introduce people to the mechanics. My wife, one of her friends, and her friend's husband all play, so I have to both DM and play at least one non-player character to make the fights more even (I made a dumb fighter who wouldn't be able to spoil the story). We just finished "Keep" and I'm about to start them on "Thunderspire Labrinyth", the next premade adventure as I'm not ready yet to create my own. I am modifying "Thunderspire" a bit, giving it some more coherency and a bit tighter plot.
It's fun, but I miss just playing. It's hard to DM because if people aren't having fun, its no one's fault but your own!