Just as in the real world, relationships change. In the ever changing online world, don't think of your accounts as memberships, because most online web applications don't seem to seem to view you as a member, just an account.
Picnik announced that it will close all free accounts, and everyone needs to gather their images before April. I wondered how this would affect Flickr, but they have a plan to have a replacement application for their account holders.
My suggestion is that you should implement the Ancestors backup plan. Have three layers of backups, especially if you believe your information is important. First, you have your original file. Second, you save this file in one other place (the parent file). Third, save the file in other place (the grandparent file). Be sure to sync those files.
Be alert to all your web applications, especially those you don't use very often. Their terms could change without much warning. Remember, it's all about relationships.