Migrate our pictures between several photo sharing sites

We have about 20,000 images at SmugMug and would like to transfer them (incl. meta tags such as title, caption and keywords) to other photo sharing sites. [login to view URL] This is a software that may do the trick but we haven't' tested it. Flickr Picasa Web Photobucket Your task is to find a software that works (not necessarily develop one), test it and supervise the whole process until all pictures are transferred.