Looks like I'll be leaving StumbleUpon.
From the page: Changes to your StumbleUpon account as of October 24, 2011
Dear StumbleUpon members,
We wanted to tell you about some upcoming changes to StumbleUpon that may affect you. Our primary goal at StumbleUpon is to help you discover great things. Our focus is on delivering you faster, better and more personalized recommendations, so that each time you click the "Stumble!" button you see more amazing content from across the web!
In order to focus on improving the discovery experience for you, and after careful consideration, we have decided to remove Groups, discontinue the ability to select Themes, and simplify Blogging capabilities. We know some of you have enjoyed having these features, but we believe that this change will allow us to better focus on making stumbling amazing for you.
Here's how these changes will take place:
Groups will be visible until October 24th, then will be removed permanently from the site. You can manually copy anything you'd like to keep, or will be able to export group information. We are working on an export option and will have more specific details about this in a few weeks.
Your current theme will remain up until October 24th. At that time all themes will be changed to a default theme that is a white background with black type. To see how your profile will look with the default theme, change your settings here.
3. Blog Posts/HTML Reviews:
After October 24th we will no longer offer HTML/Blogging functionality, but you'll still be able to access blog posts and reviews created before October 24th which will exist in plain text format. We are working on an export option and will have more specific details about this in a few weeks.
Your feedback and questions continue to be important to us as we make changes. In a few weeks, we'll provide more details around export options. In the meantime, we've put together an FAQ where you can read more about these changes. Also, feel free to reach out to us directly if you have questions.
Thank you for your understanding and support as we work on making StumbleUpon better for you!