In his song writing and also his ability to being together extraordinary musicians from around the world.
He's certainly not a strong vocalist... although he sings within his limits so his voice fits perfectly.
No, Paul wouldn't be an artist that would just pop into my mind as someone I 'must' see BUT... given the chance I definitely would go see him, with glee.
I've seen a few musicians who performed very long concerts... never leaving the stage. Amazing stamina to do that, by the way. Elton John exceeded 2.5 hours twice when I was in attendance. So did John Denver, who was on stage over 3 hours.
The are artists whom you can easily tell are on that stage because they love it... passionately.
