I guess the hardcore drug use finally caught up with him. One of the most important progenitors of rap music, Scott-Heron incorporated poetry and jazz into his music, which ran the gamut from confrontational to mellow, but was always political. He incorporated his sociological observations and opinions about racial inequality in America into all of his music. I got into his music late, but really liked his 1970's output. "Pieces of a Man" and "Winter in America" (with Brian Jackson) are 2 of my favorites. Howard Stern used Scott-Heron's "Whitey's On The Moon' for a great bit in his earlier days, and Eric Lindell did a great cover of "Lady Day and John Coltrane" (on his 2nd disc "Low on Cash, Rich in Love").
I've read interviews and articles about Scott-Heron where he talked about his drug abuse, and said that had no interest in kicking his habit. In recent years he made a few albums (2010's "I'm New Here" was critically lauded) after being "discovered" again by the owner of XL Recordings, who took a chance and gave Scott-Heron the opportunity to create new music. He was a great talent, and unfortunately died way too young. Gil Scott-Heron was only 62 years old.