Many iPhone Beta Firmware users are reporting that the latest update now features a menu that features a virtual switch to toggle between EDGE and 3G access as well as VPN setup and international data roaming.
This is the first definitive piece of evidence that leads to a new version of the iPhone featuring a 3G radio as well as both US and UK Apple Store websites listing the current iPhone as out of stock. This also corroborates recent multi-carrier agreements on European carriers, with current exclusive carriers marking down units in order to clear out existing stock.