It's still under wraps, but the report says WhatsOpen.com offers a Web application that shows people nearby stores that are open for business.
Valleywag has screenshots that show that the application appears to use a Google map mashup to display stores that are open in your area. It also looks like it includes user written reviews.
Looks like a no-brainer to me; who wouldn't want to get that kind of information on a phone based on your location? Especially if it's easily searchable and displayed on a map.
No word back from Google or WhatsOpen.com about it.