THE GEEKS shall inherit ... the A-list? Don't laugh just yet. As Twitter, Google, and Facebook become the go-to platforms for sharing information, their HQs are hosting more VIPs than ever. But all celebrity appearances are not created equal. Whereas most Twitter visits are drop-ins captured on camera phone, Google uploads its expertly staged talks to YouTube, where they've logged 16 million hits. Facebook's "Live" Q&As, by contrast, put at-home viewers first, allowing them to submit queries during events. So how do the juggernauts stack up against one another? We grade a year's worth of events — and their companion videos — to find out.