(Updated with more information at 1:45 p.m. EDT) (Corrected OpenCL definition at 10:05 p.m. EDT) At the outset of his presentation at the opening session of Apple’s Worldwide Developers Conference, Steve Jobs showed a slide of a stool with three legs to describe the company’s businesses: Macintosh, music and the iPhone. The company is making another bet on parallelism, and the implications may be