Re: Good start
Real geolocation works by analysing layer 3 messaages and trianglulating the results. It's quite good but not perfect and doesn't work too well out in the sticks. (I know this as I've just spent the last 2 weeks eveluating a geolocation tool)
Geolocation looks at all the messages,even when not on a call/active data session so it's a lot better than GPS which only works when a user has GPS switched on and is engaged in the trial.