I would say that also. It does require a lot of talent. Even if the music isn't my thing, I can see that.

True, the music is so complex, but its completely improvised at least 90% of the time...I dont think anything could be that harder to play.

Maybe Bluegrass is just as hard to play, it requires a lot of skill and focus, but Jazz as a musical form is just much more complicated, i would give it the edge, even over classical music, most musicians in that genre compromise, and they have all the time in the world to practice for a musical piece, jazz musicians are not like that, they come up with stuff right on the spot, which has to be more challenging than just playing what you read on a sheet of paper.

So true, same with blues, most of the time they change the songs around and play different progressions.

yep, im learning how to play jazz guitar, and it is extremely difficult. There is an infinite amount of things to learn about jazz, it is crazy but fun. I would recommend for someone trying to get into jazz these artists:

Miles Davis
John Coltrane
Charlie Parker
Bill Evans
Charles Mingus
Wes Montgomery
Kenny Burrell
Bucky Pizzarelli
George Benson (be careful tho, some of his stuff is awful)
Billie Holiday (if you like jazz w/ vocals)
Django Reinhardt

Now if you want some really wacky stuff here:
Miles Davis '69-70's
John Mclaughlin
Mahavishnu Orchestra
Jeff Beck 70's only
John Scofield
Tony Williams Lifetime
Wayne Shortner
Weather Report
Pat Metheny