This is a very classic Fill-in/Lick. The late great Curtis Mayfield started doing things like this with his fantastic comping style (check out Curtis Mayfield stuff - it is beautifull!!!), Jimi Hendrix was influenced then, the Temptations, the Rolling Stones, Steve Cropper, SRV not to forget... and even today young players are adopting this stuff (John Mayer).
I wrote down the basic riff in the free TABs ( http://img707.imageshack.us/img707/9903/lickoftheweek22.jpg ) - but you can find a lot more variations on this. I just played a few ideas in this video. Hope you like it - and check out Curtis Mayfield....!
Guitar: 2009 Gibson Les Paul Std. 2008, Seymour Duncan Alnico II Pro PAFs (out-of-phase wiring in middle position - very nice!). Clean only, Love Pedal Echobaby delay, 1966 Fender Vibrolux Reverb blackface original, Boss RC-2 Looper www.gregorhilden.de