CyanogenMod today have confirmed that they have started with the development of CM 11 which is Android 4.4 KitKat. CM has been one of the most stable custom ROMs out there, replicating the stock Vanilla theme of a Google device. CM currently is on version 10.2 (Android 4.3 Jelly Bean) but is still in the nightly phase. Recently they have upped the version to M1, which means Milestone version. This is between a stable and test build, has very few bugs but can be used as a daily ROM.
CM have been able to develop most parts of the ROM, but some features are a bit more tricky than others, mainly Trebuchet, Phone App and Lockscreen. On their Google Plus page they had posted that this will take a day or so more. So we can expect a nightly build by next week or two. CM have brought new life into aging devices with their custom ROMs and continue to do so! Keep up the good works guys we have your back all the way!!