I while back I wrote a blog post on Mobiforge on different ways of getting location information from the user/device (which by the way made it all the way to the mobiforge newsletter :)).
Not surprisingly, our friend device fragmentation has joined the party.
For many reasons, this kind of stuff is not so easy to solve server side using wurfl or device atlas because we are talking javascript apis and installable and/or optional software/functions in many cases.
whoisstan wrote a nice, device independent javascript that handles this very nicely. Have a look here. Nice work. I might have some contributions up my sleve as well