There’s been an explosion of iPhone applications that take advantage of a user’s location (for example, Urbanspoon, the restaurant recommendation app that was just acquired by IAC). But websites and web apps have been slower to incorporate location awareness, because it would mean having users download a plug-in or adjust their settings to share their location, and not every user will do that. Now, Mozilla and Google have taken a big step towards making geolocation a common online feature, as announced on the Google Code Blog.

Basically, starting with the latest version of Firefox (currently in beta testing), Mozilla’s browser will use Google’s Location Service to collect data from users. This is great for both users and developers — now a website can just ask users if they want to share their location, and if they say yes, the site can start using that data. So, for example, the Urbanspoon website could add the same location-based functionality that made its iPhone app such as hit. Again, the user doesn’t have to install any plug-ins or do any additional configuration.

This partnership seems like an obvious win for both companies. Mozilla, which has already been experimenting with geolocation features in Firefox, gets a more powerful browser. Google gets access to much more location data, which could presumably be useful for advertising, as well as its other location-based services such as its Latitude social network and the My Location feature in Google Toolbar, which automatically finds your location on Google Maps. (Also, Mozilla has confirmed that, unlike the Google search feature in Firefox, there’s no money changing hands for this partnership.) If we’re lucky, this could be the beginning of a wave of location-based websites.