Yahoo revealed on Wednesday a new open platform that gives users the ability to share their location data on the Web, and privacy advocates more reasons to worry about the Web becoming more of a nightmare.

Fire Eagle, as the service is called, gives users the option to store and manage information on their location, including controlling how and where their data is shared. Users will be able to authorize Web, mobile or desktop applications to update their location automatically, or do it manually from the Fire Eagle Web or mobile sites.

According to Yahoo, the service will give users great control over the information they want to share, including hiding themselves, changing their sharing preferences or deleting stored information, the Sunnydale-based company explained.

“Fire Eagle is about making everything on the Internet more useful, fun or interesting by adding the element of location,” Tom Coats, head of product at Yahoo Brickhouse, pointed out.

Fire Eagle brings something for users and developers at the same time: while users are given control over the way their share their location information, developers will find it easier to develop geo-aware applications.

Fire Eagle was launched in private beta in March this year, integrating over fifty live applications, including Dopplr, Pownce, Movable Type, and Outside.in.

The basic principle of Fire Eagle is that it doesn’t show your location unless you authorize it. Furthermore, the platform can generate location data in real time through phone GPS for example.

The service shares location information according to user preferences, by collecting it from location-enabled devices or services that have been authorized by the user. After 45 days, users will be asked through e-mail to reauthorize the sharing of their location with Fire Eagle enabled applications.

There are multiple options users can choose from in terms of updating or deleting their information. First of all, they can prevent applications from reading their location by using the “Hide Me” option in the My Privacy tab.

If they want to prevent a single application from reading their location or providing the Fire Eagle database with their location, users can choose to delete that application.

“We’re here to help people take their location to the Web by giving them the ability to control how much detail about their location they want to share and which applications they want to share it with,” said Tom Coates.

Furthermore, anyone who wants to remove previously stored location data from the Fire Eagle database can choose to delete their location info. However, that will not delete previously authorized information.

Despite the fact that Yahoo said Fire Eagle doesn’t keep history logs, and that location data stored will only be there as long as the user wants it, deleting the data won’t affect authorized applications’ collection of data stored over time.

This is where the privacy issues come in: Yahoo has absolutely no control over the data stored by their partners. This makes it extremely important for users to think well before opting-in, and although the service might prove its usefulness, there will still be a lot of users feeling sorry for choosing to reveal their location in the first place.