Announced on the CyanogenMod blog, the RC1 build represents what is likely to be the last milestone build before the full 10.1.0 release.
Head on over to the download page to see if your device is supported and download a build (or perhaps download an nightly if it's not yet fully supported). Don't forget you'll need to download a GApps package too to get your full Google-enhanced experience back.
Let us know which device you are flashing CM on and what you think of the CM 10.1 release!
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