Why ‘checking in to your favorite product’ is the next wave of social media

OK, so you know about the Foursquare-Gowalla phenomenon sweeping social media circles. These are the so-called location-based Web sites, where users broadcast their location and stores and restaurants offer them promotions. But what about checking in to products, like a box of macaroni and cheese — have you heard about this? “Checking into your favorite product is a bit different,” writes PR pro Danielle Cyr. “Unique? Yes. A bit much to digest? Yes. The next wave of geolocati…