CyanogenMod 10 builds popping up for Samsung Galaxy S III, reducing the Jelly Bean anxiety
Early CM10 builds for the Samsung Galaxy S III are being demonstrated by the CyanogenMod crew already. The Android 4.1 Jelly Bean work is in a more advanced stage for the international quad-core version of the handset, with only the camera functions sometimes iffy, and Wi-Fi tethering not working properly for now.
There are builds for the US versions as well, with more kinks that need to be ironed out, and the usual disclaimers that you shouldn't whine if something is not working outside of the issues listed when you install it, as it is not suitable for a daily driver. Getting the build on your Exynos version is pretty strightforward, as usual, just flash the CM10 zip and then the Gapps file provided, reboot and you'd be good to go.