Apple has posted a video of the keynote speech given by CEO Steve Jobs at the World Wide Developers Conference (WWDC). The video -- which is available in both QuickTime and MPEG-4 formats -- shows the introduction of two new Apple systems, and offers a preview of Mac OS X Leopard. "Watch Apple CEO Steve Jobs kick off the company's annual Worldwide Developers Conference (WWDC) with a keynote preview of Mac OS X 'Leopard' from San Francisco's Moscone West." Jobs announced the new Mac Pro and the Intel-based Xserve system prior to previewing Mac OS X Leopard.