The gold release for CyanogenMod 10.1 (Android 4.2) is very, very close, folks. The CyanogenMod team has already gone through four (count 'em, four) release candidates to date, and the fifth has just started popping up on the CyanogenMod download page. RC5 for the Sprint, MetroPCS, Cricket, and AT&T versions of the Galaxy S III are available at the time of writing, as well as the Nexus S, Nexus S 4G, Samsung Captivate, Acer Iconia Tab A700, and the Nook Tablet.
As the day progresses, builds for the rest of the officially-supported devices should start appearing on the download page. The CM team has not added anything to their Google+ page, which might mean that Release Candidate 5 isn't anything all that interesting... or just that they haven't gotten around to it yet. (They're busy people.) If you're happy with RC4, you might just want to wait until the complete build is ready.
If not, head over to the download page and check the latest releases. (The builds are coming in alphabetical order by device code name, so you should be able to get a pretty good idea of where your phone or tablet is in the list.) Those labeled cm-10.1.0-RC5 are Release Candidate 5. Don't forget to back up, and don't forget your Gapps.
Update: Builds have been posted for the Wi-Fi Nexus 7, Verizon, US Cellular, and T-Mobile Galaxy S III, unlocked Galaxy S II, Galaxy Epic 4G, the international LG Optimus G, international HTC One X, and the Nook Color.
Update 2: Builds are ready for all versions of the Galaxy Nexus, Nexus 4, Nexus 10 WiFi, Nexus 7 3G, and Nexus Q, Sony Xperia T,V, ZL, and Tablet Z, Samsung Galaxy Tab 2 7", and Tab 2 10", Motorola DROID 4, DROID Bionic, RAZR and DROID RAZR, LG Optimus 9, Optimus 4X HD, and Optimus L9, the Kindle Fire (old and new), and the Asus Transformer Pad Infinity.