We have just added some additional functionality to the new watermark feature based on our users feedback.
You can NOW change the watermark image, reposition the watermark or completely remove the watermark from your images.
To make any of these changes, simply visit the EDIT IMAGE page of your artwork and change your watermark settings for that image. Enjoy!
NOTE: These new features are only available for NEW images that are uploaded and watermarked from 4/12/12 going forward.