Sony has been one of the more supportive companies when it comes to sending its own code back to the Android Open Source Project (AOSP), and for this reason it has been a lot easier for custom ROM makers like the CyanogenMod team to port the latest version of Android to the latest Sony devices. This is why we’re now getting an alpha version of CM10 for all Sony Xperia devices that were launched in 2011.
CM10 is the Jelly Bean version of the CyanogenMod ROM, and according to the CM team, it should work on most or all devices that supported CM9/ICS. While the CM9 ROM is still not final yet, even though there have been 9 months since ICS was made open source, I think we’re going to see CM10 rolled out a lot sooner for many devices, than CM9 was.
CM9 and ICS were major upgrades for Gingerbread devices, and a lot of code had to be rewritten. This has made both manufacturers and custom ROM makers come out with a stable ROM a lot later than they normally would. But Jelly Bean and CM10 are pretty minor updates, and there’s not a whole lot of code that needs to be changed. This is why we can expect the stable CM10 version to be released a lot sooner, not only for Sony Xperia devices but for others as well.
If you own a Sony Xperia device from 2011 or later, and want to try the CM10 alpha ROM out, here’s the full list of Sony Xperia devices with links to their specific CM10 ROM: