What you're referring to is the Contacts app (which happens to have a clean, standard-themed interface on the iPhone, though I believe it does have a leather-themed interface on the iPad). The "Find My Friends" app is a new buddy geolocation app from Apple released (in the App Store) alongside iOS 5; it's similar to Google Latitude.
Isn't the purpose of a Rolodex to "find my friends" ? I believe that's what they were going for. It's weak, sure...
Find My Friends displays their current location on a map using GPS. The analogy to a Rolodex is pretty weak.