Google Maps v3 (in beta) already utilizes the sensor variable - so I dont see how this is advantageous for a mobile website.
As for desktop apps - Google also has an API function to determine your ___location based on your IP. But I dont think it utilizes Firefox's geo-___location ability.
<em>What is the benefit of this API compared to whats already available?</em>
To me, in the context of mobile websites, it provides an answer/option to providing localized content. Given you have/want localized content/filtering of course.
Where up until now, the first answer to 'You want GPS ___location?' would have been 'You'll need a native app.', it's now possible to just built a webapp instead.
At least for requests that came our way for building native apps for the iPhone, the most requested feature was 'ZOMG, make it localizable!', where the rest would be just pulling data from a server.
Now, my option is to just built a mobile webapp that can use the lat/lng without much fuss (still needs to degrade gracefully in case of older phones/browsers of course).
Very cool-looks like this is the same code that is used in Google Maps for ___location awareness in Firefox. It doesn't seem to like Opera (or it could be my connection not being found) but it seems to be cross browser compatible.
How does FF 3.5 get the ___location? The example asked me to share ___location, but then showed me in the middle of New York City when in fact I am in Burlington Vermont
FF 3.5 uses your IP address or wifi basestation id to retrieve the ___location and there is no guarantee that is accurate. In order to be accurate you need to use GPS or Cell Tower Locating from you cell phone.
The service they use is particularly bad then. Most places I have tried get within a few towns for my office. (Obviously none can get my home satellite connection correct)
<em>What is the benefit of this API compared to whats already available?</em>