Watch the Scotch 'n Soda online guitar lesson by Robbie Calvo from The Rhythm Architect
Here we are laying down the foundations for a very solid R&B groove that other players and yourself can build upon. It's basically a I7-IV9-V9 chord progression with some added chromatic sevenths thrown in for movement and interest. Check out the little nuances though, like the hammer on sus 4 on the A7 and the glissando into the D9 chord.
Another cool vibe on this guitar part is how the G7, G#7 chromatic chord move up to the A7 feels like it bounces. Play along and you'll see what I mean. Dynamics also play a very important role in the feel of any guitar part so be aware of that when you are jamming to the groove.