This week Google threw its hat into the photo-commons ring with by announcing its newly upgraded Picasa Web Albums service. Users of Picasa now have the option to individually license their photos on the site under any of our six licenses, and can also set their profile to default to a particular one:

Just look for edit button next to the “All Rights Reserved” text on the right side of any photo page, and the “Photo Usage & Licensing” section in your profile settings (requires Google Account) to set a default license.