Mozilla have recently announced the Geode project, a new experimental add-on with a build up to being fully incorporated into Firefox with the 3.1 release.

This new add-on uses a technology called Loki from Skyhook and can work our a computers location from available nearby wireless networks to within 10 - 20 metres accuracy.

The system does stay in control of the users however, when a website requests the location of the user, a notification bar lets the user decide whether or not they give their precise location, the general area that they are currently in, a more general city/town location or you can choose not to share this information at all.

The implications of this for Local SEO are possibly massive. At present a lot of local search intent has to come from the phrases that you use when searching in an engine.

Matt has mentioned before, about 40% of all searches have local intent, and if engines and browsers can better identify the position of the user, then it can only help to serve them more relevant results to use.

It remains to be seen how the search engines can start using this data, but it will be interesting to see it develop.