Team Douche began pumping out nightly builds for CyanogenMod 10.2 last night, bringing the Android 4.3-based goodness to quite a few supported devices. Initially supported devices include the Nexus devices, the Galaxy Nexus on VZW, the Bionic, the One on all carriers, and the Galaxy S4. More devices will be supported in the future, but of course these things take time.
You can expect to find bugs here and there, given that these are nightlies, but remember that they are not looking for anyone to submit reports.
Grab the latest CM nightlies from the official get.cm website for your device.