Why is American Idol so Popular?

So the numbers are in and American Idol has bested itself. Although I think American Idol can be quite the fun show to watch, I'm interested in why it is so popular. I have a few theories and I've read a few theories that I will share here, but I'm interested in everyone else's opinion.

1) Audience Participation--the audience gets to play a very active role in determining the next American Idol. Once the top 24 are chosen, the audience decides who they think are worthy of going on. And there's still some element of surprise, last year's winner Taylor Hicks was not supposed to even make it into the final group as called by Simon. And Chris Daughtry, favorite to win by many, actually finished fourth.

2) Limited Engagement--Fox only runs this show once a year. In so doing, they keep it very fresh. You don't get tired of seeing it a million times a week (i.e. Law and Order, CSI, Survivor, etc.)

3) Family Friendly--Although not perfectly family friendly, it's far more family friendly than many, many other shows.

4) Community--American Idol message boards are wildly popular and unlike scripted television shows, fans can band together in action to try to vote their favorite idol on. Plus, there's the whole watercooler thing.

5) Success--Many past idol contestants have had quite a bit of success, and this year, Jennifer Hudson just won a golden globe. These people are actually making a splash in our popular culture. If you miss Idol, you miss the place where it all begins.

So those are some of my theories, and I'd love to hear yours...Did you watch last night?