Wow... There is so much goodness going on in that clip, even irrespective of the context of this thread. (Steve Gadd's drumming, holy cow, is there anything he can't do while making it sound absolutely perfect?) But yeah, Jimmy Johnson's tone is fantastic, it's like everything you would ever want from a bass sound, but then just a little something extra...there's an articulateness (?) that allows you to hear every single note with equal clarity, and that's really hard to get from a bass that doesn't also sound too bright or too twangy.
And his lines, omigod, Jimmy Johnson is rapidly becoming one of my favorite bassists. So tasteful and musically informed, never inappropriate or showboating...until the music calls for it, and then he's all over that!
Okay, sorry, swoon over.