Just listened again to Jesse Cook and his live concert at the Jazz festival of Montreal... I don't have an opinion on who is the best guitarist, but he is most surely one of the best. Just listen to this and this. If you like guitar music you will like it.
Hm. I've never thought of being a good guitarist as being able to play insanely fast, or overly complicated things. I find that if they can't play good, they fail. Complexity and speed are nothing if it doesn't sound good.
Iron Man by Black Sabbath has easily the best riff, ever. Hands down. Yet anyone who has more than an hour of real guitar playing experience can play it. That's good, not speed or complexity. Sure, they can sound good AND be fast and complex, but that isn't the essence of guitar playing.
Top of my list is Tony Iommi, the guitarist for Black Sabbath. He can play excellently, and write excellent riffs at the same time. His solos are fantastic, yet they aren't insanely fast most of the time. They're just awesome.
If you wanted to count speed into the mix Kerry King and Jeff Hanneman are good in this area.
I'll have to add Tom Morello. His solos are great and his style somehow unique, when you hear him playing you know it is him and no one else. That for me makes him one of the bests too.
Can't name the best but some of my favorite guitarists are (in no order):
Joe Satriani (If you don't know him you nothing about anything) Travis Stever (Coheed & Cambria) Michael Angelo Batio (Nitro) Brian May (Queen) Randy Rhoads (Quiet Riot) Jack White (White Stripes)
currently the list stands like this on best of the best.
1 buckethead, no one is even on the same level as that guy right now 2. john petrruci 3. Michael angelo batio 4. john mayer, im sorry but i think hes better then jimmy (this one is arguable) 5. carlos santana
I dont remember well but there was a poll about fastest guitar player on Guitar Magazine and Impelliteri won (im not 100% sure ) and the next 3 (i dont remember the order) were Malmsteen, Stump, Batio; Petrucci and The Great Kat were too. I dont think Batio is the fastest but for sure one of the fastest and is known cause of his 2 hands tech (so amazing)
Speed is not really all the stuff, quoting... Satriani? haha well some good guitar player, "is not about playing a scale fastest posible, its about making music with that scale".
Buckethead is Paul Gilbert's student and is know cause of his "robot" albums and sound XD, check Welcome to Bucketheadland or Giant Robot, he got a good acoustic album too Colma, really nice songs there. I dont think is a techno guitar player XD instead more related to experimental rock.
Is really hard to decide the greatest guitarist just cause of styles and there are more than 1 criteria to value too. So is more about own perspectives and mass-media trends.
Rolling Stones magazine already did this list before: 1. Jimi Hendrix 2. Duane Allman of the Allman Brothers Band 3. B.B. King 4. Eric Clapton 5. Robert Johnson 6. Chuck Berry 7. Stevie Ray Vaughan 8. Ry Cooder 9. Jimmy Page of Led Zeppelin 10. Keith Richards of the Rolling Stones
You can agree or not but this shows that same, is kinda pointless to make lists without a particular approach (lets call it, academic) to the topic. Beyond that is just entertainment.
Its curious how The Yardbirds glued together 3 great guitar players, Eric Clapton, Jeff Beck and Jimmy Page (they didnt play at the same time =/) and George Harrison and Duane Allman were Clapton friends. By the Bluesbreakers time Eric Clapton "was god" but then Jimi Hendrix appeared and you know the rest of the history. And Hendrix was connected to Satriani as well (he started to play when Hendrix die) and his death affected Eric Clapton so bad too =/ he wante to give him a guitar for his birthday. (im not sure the date)
Even if Van Halen is more a glam guitar player, he gonna be remembered cause of the tapping technique in Eruption, that fact cant be denied; and for example that Stevie Ray Vaughan helped to the boom of blues-rock. I gonna mention Yngwie Malmsteen, cause he is a good example of "do it for yourself" and of course he gave to the neoclassical rock the neoclassical part.