Developers on the XDA forum have been working hard to compile CyanogenMod 10.1 and 10.2 for the Xperia U but now that Android 4.4 sources are up and CyanogenMod is pushing CM 11 code to its github repository, developers are more focused on getting CM 11 working for the Xperia U. Since CyanogenMod 11 for the Galaxy S3 Mini has already been compiled and owing to the fact that the Xperia U and S3 mini are built on Novathor chipset, development of CM 11 for Xperia U becomes much easier. Galaxy S3 mini developer New Maclaw, Gava97 and munjeni are working together on this ROM and today, I decided to give this ROM a try. Why today? Good news is that WiFi and camera have been fixed in the latest build and it also seems like GPS is working.
The ROM is still in development and has many bugs at the time of writing. These bugs will be solved when CyanogenMod team starts rolling out nightlies of CM 11 for other devices and probably some features could be ported to the Xperia U too. It is important to note that as of November 24, the ROM is not suitable for daily use but the work developers have done in bringing CM 11 to this little device even before and official nightly is out is appreciable.
I tested this ROM on my Xperia U today and couldn’t get ART (Android Runtime) working on the device. All apps run on dalvik runtime. Switching to ART in Developer options force closes Google apps which is probably because the Gapps I used are Paranoid Android Gapps. This should be solved when the CyanogenMod team releases Gapps officially. Camera force closes when you take a picture. WiFi works well but bluetooth doesn’t.
While those were the major bugs, you can refer the original thread on XDA for other minor bugs and downloads.