Properly upset by this. For me he was the definitive voice of modern fretless bass; his work with Brand X, Kate Bush, Judie Tzuke, John Martyn and so many others moulded my own approach to the fretless instrument in a big way. For many people, Jaco was the ultimate fretless master; for me, it was this guy. Check out the mid part of this song, beginning at 2:22, and you'll see what I mean. Those fills give me goosebumps.
Rest in peace, maestro.