This is still very early days, however it does appear as if the Cyanogen team has begun working on CM11. Or more specifically, CM11, which is based on Android 4.4 Kit Kat. Getting this out in the beginning, the team hasn't offered anything in terms of dates just yet, but they have offered some basics in terms of details.
Coming by way of a recent Google+ posting, the folks at Cyanogen have said they "have begun the initial push of CM 11 (Android 4.4 KitKat) branches and code to our repositories." Again, this doesn't mean anything is available for use just yet. In fact, it may be some time before a ROM arrives for a wide variety of devices.
To that point, as we have seen in the past, it looks like the first devices will be Nexus branded. A posting in the comments asked for the initial device list and the reply was a simple Nexus." Otherwise, there was talk of some features and it was said that "a lot" of the features survived the jump to 4.4, but a "handful" did not make it.
The Cyanogen team hasn't offered a full list of those impacted features, however they have said some of the items include Trebuchet, the Phone app and the Lockscreen. Otherwise, aside from looking forward to CM11, there is still plenty to enjoy with current builds. We recently saw the release of CM10.2 M1 which arrived with support for more than 70 devices.