You can now update your DjangoSites website screenshot by simply editing your listing and ticking the box that says "Re-do Screenshot".
To edit a website, first log in to DjangoSites using your username or OpenID. Once logged in, click 'My Sites' in the navigation bar, then click on the website you wish to have updated.
From the website detail page, click the 'Edit' link next to your username. Make any changes you wish to make, click the Re-do Screenshot checkbox, and click 'Save'.
It's important to note that when you edit a website, it becomes un-verified so it will not be publicly visible. I manually review all submissions and edits, so it might take me a few days to verify and publish your listing after you edit it.
This is something that has been on the books for a while, and I'd like to thank Richard Barran for prodding me into getting the change done.
While you're editing your listing, you can update your deployment details to help with our Django Deployment Survey. The results will be published shortly for all to see - thank you to those who have responded so far!