There will be many potential purchasers who start jumping up and down at the prospect of finally being able to do Voice over IP. But don't get too excited too quickly.
The BlackBerry 8820 supports UMA rather than SIP. Without getting too technical, it is the SIP protocol that you'll find in mobile devices which let you use free VoIP services like Fring. The UMA protocol is more closely tied in to your mobile network and whether or not you can make VoIP calls will depend on what they are prepared to allow. The network will be in control. Orange has a service called Unique which is compatible. The good thing is that if you do have the facility, the 8820 should be able to switch automatically between Wi-Fi and your GSM network for voice and data.
The Wi-Fi setup routine on my review sample was specific about the fact that it could be used for web browsing and mobile email only. It found my network easily and I was indeed able to use it for these two purposes. RIM has added a Manage Connections utility to the 8820 and so switching Wi-Fi, the also present Bluetooth and GSM on and off is extremely straightforward.
