The Tallest Man on Earth - he's a great acoustic player and loves playing around with alternate folk tunings (think Joni Mitchell + Dylanesque vocals/intensity)
David Longstreth of Dirty Projectors - awesome guitar player who loves funky rhythms oft-inspired by African music
Amadou of Miriam & Amadou (Mali blues musicians are some of the best around) - this act has me especially interested seeing as how the Malian government has issued a ban on secular music
also, I'm sure Sir Paul has a fantastic touring guitarist, although idk know him by name or anything
Actually Paul has been touring with a duo of two guitarists the last 10 years or so - Rusty Anderson and Brian Ray and they're both really good. I wouldn't be surprised though if his kid plays (he's played with him before) since he will be in the area.