FlickrSync is a free desktop application for Windows XP and Vista that allows you to synchronize photos from your computer to Flickr. FlickSync displays local folders on your computer, your online Flickr sets and establishes synchronization rules between them.

Key features of FlickrSync include:

-Browse local folders and flickr sets and match your local folders to the corresponding flickr sets.
-Create new Sets when uploading new folders.
-Define flickr permissions for each folder and other synchronization options
-Preview all operations (including photo thumbnails) before applying them to flickr.
-Synchronize specific folders or all selected folders
-Synchronize all image information, including metadata like title and description, keywords/tags and even geo information.
-Use different synchronization methods according to your needs (ex: by date taken, by caption, by filename).
-Define optional filters for each folder. For example: only synchronize to flickr images that have a certain keyword/tag on a specific folder.
-Support for all flickr image formats
-Support for Windows Vista (including Picture Gallery tagging and caption)

Download FlickrSync for Windows here[codeplex]