Migratr is a cool little freeware Windows application that lets you bulk move your photos between different online photo services.
We all are pretty into Flickr, but Flickr's free account only serves up 100MB of storage space. So if we want to move to the 1GB pastures of an integrated Google service like Picasa Web Albums, Migratr comes very handy.
Migratr supports importing and exporting to and from Flickr, 23HQ, Zoomr, SmugMug, and Picasa. The best feature of this application is to preserve meta data associated with the pictures while swapping from one service to another. It preserves each photo's title, description, tags, and albums.
The cool thing about Migratr is that you don't have to use it to just "migrate" photos. It also works splendidly as a simple downloading and uploading tool for any of the supported photo-sharing services. To use it as a local uploading tool, simply skip to step 4, select your photo service, then pick the local directory full of images you want to upload, and you're good to go.