Thom Yorke's inclusion in the list (which also includes such Apple luminaries as iPod and MacBook designer Jonathan Ives) means the Radiohead frontman is seen to "help build public perception of what Apple 'is' as a cultural force".
What? How? Well, by using the company's products, often in public. While Thom and the rest of the band famously eschewed Apple's iTunes store until very recently (refusing to have their albums sold on it), they've been more than happy to make use of and/or even 'endorse' Apple's other products. - Here are just a few examples