Windows Phone 8's Live Tiles are its "heart and soul," program manager Joe Belfiore said. STORY HIGHLIGHTS Windows Phone 8 Apollo unveiled at Microsoft's phone summit Newly announced features for operating system included a new start screen Phone will run on powerful dual-core processors System will also include a new Wallet hub for payments (CNN) -- It's shaping up to be a huge week for Microsoft. On Monday, the company announced its Surface tablet platform at a hush-hush event in Los Angeles, and now Microsoft has unveiled Windows Phone 8 Apollo at its Windows Phone Summit in San Francisco. Microsoft announced eight specific platform updates for its upcoming mobile OS. We've already covered one of the…