Give feedback: "Like"
Comments aren't the only way to give feedback in Picasa Web Albums. Click the Like link below the photo or video to let the owner know what you think. The number of users that like a photo or video will be visible to anyone that has permission to view it.
You can only vote once for each photo or video -- you either like something or you don't. To remove your "like" vote, simply click the resulting Unlike link.