Who'd a Thunk It?

When did Jack Johnson become a musical powerhouse?  His Sleep through the Static has sold over 375,000 copies, which is quite respectable these days.  While his nearest competitor for the week was Sheryl Crow who did not even break 100,000 copies for Detors!

I am not quite sure what to make of this?  Maybe it was that Curious George soundtrack he did.  Or maybe the music industry is shifting?