If you keep your device updated with the CyanogenMod 10.2 nightlies, you should stay away from it for sometime. No, we are not saying that CM team is trying to ambush you with some kind of malware or any other threat. It's just something went wrong on their Sept 7th nightly release and it is advised to not to flash the recent update on your device -- no matter how appealing it might be.
CyanogenMod team warned all the followers on Twitter, Facebook and Google plus about the issues you might experience after flashing the recent nightly build.
Many users reported on the official CM forum that they can't boot into their device after flashing the latest build released by CM team and they had to revert back to last working version. Preferably, you should stick to the September 5th nightly release, which is last working version released by the Team.
We hope the CM team will be able to fix this issue on their next build and the service will be resumed to be normal. Nightlies are test version of the final release of the device which lets the developers to pin point all the bugs and errors. It is adviced not to flash the beta releases and release candidates on your device, unless you really know what you are doing. Untill then keep yourself away from CM 10.2 nightly released on 6th and 7th sept.
[Source: Google Plus]