AT&T’s BlackBerry 8820 has been officially announced today, packing both GPS and Wi-Fi under the hood and hitting store shelves tomorrow. The 8820 will also be coming bundled with AT&T’s Mobile Music, which gives access to XM Satellite Radio, among other music services. You’ll have to fork over $299.99 on a two-year contract for this beauty. This wasn’t exactly the soft launch we were thinking of, but quietly getting the devices into stores for a nearly day-of announcement is a pretty good way of building up hype. After all, which announcement gets you more excited: “It’s coming next week”, or “It’s coming tomorrow”?