I'm late on the Zawinul memorial train, but as a keyboard player it's hard to avoid his influence. I've never been a huge Weather Report fanboy, but I remember when I bought 8:30. I was blown away by the orchestral scope of sound four musicians created live, and attracted by the balance of strong melody, lyricism, and almost pop-like triadic harmony with intricate rhythmic interaction. Zawinul's choice of synth patches always struck me as more vocal (even leaving his penchant for the Vocoder aside) than Chick or Herbie which, as great as they are, reflected a sort of guitar envy. I still can't fathom playing a keyboard backwards; Zawinul's WR rig famously contained an ARP 2600 with a reversed voltage control to allow him to play the keyboard backwards.
Given the majority of his reputation was made in his electric settings, it's a pleasant surprise to listen to his early work with Cannonball, before the Rhodes and Wurlitzer made an appearance on his frontier. His accompaniment work on the Nancy Wilson/Cannonball Adderley record is sublime.
As usual, Darcy's got the compendium of tributes. My heart sinks for Zawinul's family, and for Wayne Shorter.