With the level of anticipation surrounding Jelly Bean and CyanogenMod 10, pretty much any news of a working build is good news. Today, test/preview builds of CM10 have surfaced for Motorola's Xoom as well as the ASUS Transformer and Transformer Prime (tf101 and 201).
Of course, since these are preview builds, they aren't perfectly stable. It's also worth noting that unofficial builds carry no guarantee of support or update.
That being said, the Transformer builds are surprisingly functional with Wi-Fi, Bluetooth, sound, camera, video acceleration, some dock functionality, and most sensors functional. GPS and light sensor functionality isn't quite there yet, but most of the device's critical functionality is present. Here's a quick video of the build in action.
The Xoom builds, on the other hand, are not quite as complete. In a post to Google+, Steady Hawkin notes that "a lot of the features and functions are still very much [a work in progress]." Hawkin also notes, though, that he has personally been using the builds as a daily driver, meaning they may just be worth checking out.
To get a hold of an early CM10 build for your device, just hit the appropriate link below.