Great point Dontomasso. Dylan is one of the most prolific artists in rock history. While the Stones keep releasing albums and have been around nearly as long as Dylan, they are essentially a "greatest hits" band that tours on their past glories. That's not a shot against the Stones, but they've been making essentially the same music ever since Brian Jones left the band. Dylan keeps trying new things.

Springsteen has been following Dylan in a similar vein with different outlets. He has a couple of folk-style albums (The Ghost of Tom Joad and Devils & Dust) as well as a cover of old folk classics (We Shall Overcome). But even Bruce can't hold a candle to Dylan's changes in style and output of released music. I think Bruce is trying to catch up, but the Boss went many years between albums for a good portion of his career trying to release great "albums" instead of a collection of songs (not that I'm at all implying Dylan does the latter).