Update: Stable builds for many more devices are now showing up on the CM download site. Hit the source link to view the growing list. Additionally, an update by the CM team on Google+ confirms that CM10 stable builds are rolling out, and namedrops the next major version of the ROM, based on Android 4.2, as CyanogenMod 10.1.
Original: We've yet to see any official announcement, but the CyanogenMod download site is currently populating with stable builds of CyanogenMod 10. The Jelly Bean-based custom ROM reaches the milestone as the Galaxy Nexus and Nexus 7 get their Android 4.2 updates, and Nexus 4 and 10 go up for sale around the world.
At the time of writing, stable CM10 is available for the Sprint and Verizon Galaxy S3, LG Optimus Black and Samsung Galaxy S2 Skyrocket. More are likely to follow in the coming hours and days, so we'll be keeping an eye out for the official announcement.
If you've tried one of the stable CM10 builds, hit the comments and let us know how you're getting on!