Today Adobe is announcing a public beta of the all new Lightroom 4, available as a free download from its website until the full version goes on sale in "early 2012." This release includes major changes to existing photo management, editing, and sharing features, while adding in tons of new features as well. The release is also the first to drop support for Windows XP, though it still works with Windows Vista, Windows 7, Mac OS X Snow Leopard, and Mac OS X Lion. Interestingly, however, it doesn't work in Lion's native full-screen mode.

Lightroom 4 beefs up support for video files, allowing users to trim clips nondestructively and extract individual frames as JPEGs. Editing adjustments can now be applied to both video and stills, and Lightroom 4 has all new basic controls for highlights and shadows to extract the complete dynamic range from images. There are also new local adjustment controls, which let users to edit specific regions of an image for items like white balance or noise reduction.

Late to the geolocation game, Lightroom 4 adds in robust geolocation support for images and videos, finally catching up with more consumer-oriented apps like iPhoto and Picasa. Users can add locations manually, or use data from dedicated GPS devices to sync their photos to the software's built-in Google Map. Adobe may also be looking to sway iPhoto users with Lightroom 4's photo book creation tools that occupy a new tab in the app's interface. A variety of templates come pre-loaded for quick and easy layouts, and a partnership with Blurb for printing means books can be ordered with a single click from directly within the app.

Once photos are edited, a new publish services pane allows users to upload to the web without having to export first. Adobe includes support for Facebook and Flickr, and hopes developers will write plugins for other services. This version of Lightroom also has a built-in email client, mitigating the need to export and email separately. Finally, Lightroom 4 is the first version to support the Digital Negative (DNG) "lossy" RAW file format, which promises to maintain image quality and preserve Lightroom metadata, while shrinking the size of RAW files by up to 75%.

To try out the beta for yourself, head over to Adobe Labs to grab the free download.