Mozilla on Tuesday launched another new experimental Firefox plug-in that adheres to the nascent W3C specification for geolocation APIs, and that's built to understand and manage users' location information.

Mozilla Labs' new Geode add-on communicates with sites that want to know where the user is, passing along as much or as little data as the user wishes to allow -- city, neighborhood, or exact location.

Exact location in this case is pretty exact. Geode's using Skyhook's Loki location service, which triangulates your position from nearby Wi-Fi signals. Mozilla's tests claim that Geode can lock in your spot within 10-20 meters, and in just a few seconds as opposed to the minute or so a more traditional GPS might spend gaining its bearings.

Mozilla's a member of the team hammering out the details of the World Wide Web Consortium's Geolocation API Specification proposal, which would stipulate an interface to location information gathered by or transmitted from the hosting device (for instance, a program or something running in a browser window). The API wouldn't specify how the location info is gathered -- Wi-Fi, GPS, IP address, whatever.

The spec is in draft form for now, but participants don't want to sit on their hands; the editor's page currently managed by Google's Andrei Popescu warns the tardy that "Implementers who are not taking part in the discussions are likely to find the specification changing out from under them in incompatible ways."

Some of those implementers are pretty busy, though -- for instance, Mozilla is not only putting out Geode but working on geolocation services for Firefox 3.1, of which Geode will be a part -- directly or indirectly. In that upcoming browser, a user can choose whether to have her or his system pick up location data from an actual GPS, to let Web-based services such as Geode take over, or to provide the information in some other fashion. As one of Mozilla Labs' "little experiments," Geode is built to help the larger product along as well as to aid in the development of Fennec, Mozilla's mobile browser.

One of the issues on which Geode should help to focus both browsers' geolocation services is privacy -- which is, naturally, a serious issue in any discussion of geolocation, or of Mozilla for that matter, according to Mike Beltzner, director of Firefox.

Loki was chosen in part because it allows Geode users to see and specify how granular they're willing to get with their information, according to Beltzner. Loki itself retains only anonymous, aggregated data. "But still that may be too much for some users," he says. By the time 3.1 launches, Mozilla's goal is to have multiple geolocation options, including at least one that retains no information whatsoever, all using the API-to-be.

Enjoy it while you can, add-on fans. As usage data and feedback about Geode itself accumulates, Beltzner says that the team developing Firefox 3.1 (currently expected to hit first-beta stage next week) will evaluate what's working and make decisions about implementation. Eventually, he says, Geode, or good ideas garnered from it, will simply melt into the browser.