Oh damn. Yes this is very sad indeed.
One of two jazz musicians who I felt artistically and intellectually unqualified to listen to for many years before finally digging into his iconic discography (the other was Thelonous Monk).
I still feel that claiming to understand or fully grasp Coleman's music would be hubris. He was a true pioneer of experimental music, and one of the founding fathers of the musical avante grade.
He will, of course, be missed.