Steven Tyler became a rock idol in the 1970s, long before reality television even existed. And now he's joining 'American Idol,' the biggest reality show to ever hit these shores. As a judge, he'll help America choose its next 'Idol' through a competition. It's certainly a different journey.

"I always thought that in order to become an American Idol, or any kind of idol, you have to pay your dues," Tyler said on 'Late Show,' referring to the years of national touring he did with Aerosmith. "But, today's a different world."

"I prefer the process that gave us you to this process," David Letterman said of 'American Idol.' "By the time you're ready, you're ready, and we have the honest, legitimate stamp of approval."

Tyler responded, "I tend to agree," which was enough to get uproarious applause from the crowd. Surely FOX couldn't be too pleased that one of their newer high-profile judges is basically saying he doesn't think this is the best way to find a new music idol? See the video after the jump.