This morning, the CyanogenMod team okay'ed the next "stable" release of CyanogenMod 11. This is CyanogenMod 11 M8. Now these aren't actually milestones, or monthlies, even though they are released each month. But they are more stable than the nightlies, so those looking to run a stable version of CyanogenMod on their device are going to want to check these out. The build bot is rolling out the M8 release for all supported devices, so if you're device isn't there quite yet, don't worry, just give it some time and it should appear shortly. As far as the changelog goes,
"Common: Android 4.4.4 (Google), New Devices: Sony Xperia Z2 (sirius); Xiaomi Mi2 (aries); Oppo Find 7a/s (find7); OnePlus One (bacon), Common: Fix VPN issues related to 4.4.3 merge, Common: Enable 'Heads Up' notification mode (Settings > Notifications), Settings: 'Interface' replaced by 'Status Bar', 'Notification Drawer', and 'Gestures', Settings: Moved 'Expanded Desktop' to 'Display', Settings: Moved all lock screen related items to 'Lock Screen' and removed duplicates from 'Security', Settings: Moved 'Navigation Bar' layout control to 'Buttons', Trebuchet: Custom Homescreen grid size, Trebuchet: Add Protected Apps feature, Trebuchet: Add Search Panel (Google Now) option, WhisperPush: No longer ignores 'Blacklist', Futex: Protect against Towelroot, Various small bugfixes, global and device-specific."
So if you're running CyanogenMod on your device, you should see a notification for an upgrade pretty soon. And those waiting for release candidates and stable builds, well they aren't coming. CyanogenMod announced a little while ago that they are only going to be doing nightlies and these "M" releases. So this is about as stable as you're going to get. CyanogenMod did say that this M8 release is based on Android 4.4.4 which is currently the most recent version of Android. As they aren't working on Android L until the code is out and the official release is out. They will not be working to port the Android L developer preview over.