For you themers who want to show off your themes designed for the new CM 11 Theme Engine, options are somewhat limited now. For example, your users can try searching for “CM11 new theme chooser” themes or use similar search phrases in the Play Store and get mixed results, they can join the CyanogenMod Theme Engine Alpha community in Google+ and check out the new Themepark section or take a gander at our new 2014 CyanogenMod Theme Chooser forum. Unfortunately, they’ll either find an incomplete list of themes designed for the new engine or they’ll have to take the added step of joining a Google+ community they may have never heard of.
The good news is that Cyanogen Inc. will soon be releasing the Theme Showcase app, which we mentioned before along with steps you need to take to have your themes included in it. We now have an official release date of June 16 for the CyanogenMod Theme Showcase, which also gives you a rough timeframe for finishing your themes and submitting them if you want your work to be included in the initial launch. By way of reminder, the instructions for submitting your theme to the Showcase are found here (you’ll have to join the CyanogenMod Theme Engine Alpha community to see the instructions and the official theme template).
Source: Brian Resnik (Google+)