Cyanogen is doing a bit of an overhaul to their Operating System for their upcoming release of CyanogenMod OS 12. We have already got a glimpse of the new boot animation and today they showed off the new Themes app. The themes app allows for themeing of individual apps. This will allow you to change the theme and color scheme of any app on your phone. This way if you have a theme that you totally love that doesn't theme one of your favorite apps you can go in and change the theme of the app to match the rest of your theme.
Cyanogen also mentioned that paid apps would be supported in CyanogenMod Os 12 as well. This is good news as being able to charge a slight amount gives some motivation and reward for great themers to keep on theming.
via cyngn.com