RIM improved their location services that they offer devs this month with the addition of Wi-Fi geolocation. Originally devs had to use GPS to find your location and then RIM added the ability to get your location from cell phone towers (Cell Site Geolocation) a year ago. Now devs can also get your location based on the Wi-Fi network you are connected to. RIM collected this information anonymously from BlackBerry users to enable the feature worldwide.
Wi-Fi geolocation nicely compliments the GPS and cell tower location services and should help devs get a quick location on OS 6.0+ devices. Check out more details about the service and API’s on RIM’s devblog. Some apps may already be setup to use this service as Ebscer points out on Twitter if they are using the Optimal Geolocation mode.