This change was made after numerous requests. This will not affect any droplets you have currently running the RoR one-click image and if you wish to use the MySQL based RoR image in the future you can do so by doing the following:
1.) Create a new RoR droplet on your account. For this purpose I recommend a 512MB droplet.
2.) Power off the new droplet and create a snapshot image from the control panel
3.) Destroy the droplet
This snapshot image will remain on your account and allow you to continue spinning up droplets using the MySQL based stack. As this image will no longer receive updates you will need to make sure that when you launch a new droplet from it you run
apt-get update and
apt-get upgrade to install any security updates.