Users are reporting that WiFi-only iPads (which do not have GPS natively) are able to accurately pinpoint their location on a map when tethered to an iPhone through the personal hotspot feature. There is no easy way to determine if the iPad is truly being fed GPS data from the iPhone, but the geolocation information when tethered is far more accurate than standard WiFi positioning. This gives users who own both devices—and rarely separate them—a good reason to save cash and opt for the cheaper model.
The only features that separate the WiFi and 3G iPad are the addition of the 3G and GPS chips (and $130), but tethering to an iPhone nullifies both these points. With the original iPad now cheaper than ever, it could be a great time to pick one up. iPads tethered to a GPS-capable Android phone (or anything other than an iPhone) do not seem to benefit from this feature.