I've been playing since release and still enjoy it. It doesn't have as much of a variety in content as other MMOGs though. There are no tradeskills, no loot, and no economy. The game is mostly based around fighting and action, but it does do that well.
For me, the big drawing point of City of Heroes is that it does the story a lot better than any other MMOG I've played. As you level up, you learn more and more about the story of the game, revealing a lot of twists. Some nights I've stayed up late just to learn more of the story.
They did give out free 14 day buddy passes for Labor Day, but unfortunately I didn't get mine. If you know someone who plays City of Heroes, maybe they'll have one for you.