While I appreciate Adobe letting us use their service without any apparent cost, you should read the fine print…
From the Photoshop Express terms of service :
8. Use of Your Content.
1. Adobe does not claim ownership of Your Content. However, with respect to Your Content that you submit or make available for inclusion on publicly accessible areas of the Services, you grant Adobe a worldwide, royalty-free, nonexclusive, perpetual, irrevocable, and fully sublicensable license to use, distribute, derive revenue or other remuneration from, reproduce, modify, adapt, publish, translate, publicly perform and publicly display such Content (in whole or in part) and to incorporate such Content into other Materials or works in any format or medium now known or later developed.
2. “Publicly accessible” areas of the Services are those areas of the Adobe network of properties that are intended by Adobe to be available to the general public. However, publicly accessible areas of the Services do not include Services intended for private communication or areas off the Adobe network of properties such as portions of World Wide Web sites that are accessible via hypertext or other links but are not hosted or served by Adobe.
While they don’t claim they own your images, it sounds like they can do whatever they want with them, without even a “please” or a “thank you”.