It hasn’t been long since Android v4.4 KitKat was introduced by Google with the Nexus 5, and we already have a Chinese device running the same flavor of Android!
Although this is not an official build, MIUI forum member @秋叶随风 managed to get Android v4.4 KitKat running on his Xiaomi Mi2. The Mi2, like other Xiaomi phones, comes with the companies own take on Android, known as MIUI. The latest version of MIUI, MIUI V5 is based on Android v4.1, which some users see as outdated. However, Xiaomi feel that Android v4.2 and v4.3 do not have significant changes for a re-base of MIUI. Have a look at some pictures showing the device running KitKat:
We can’t say for sure if this is a port or a build, either is possible after Xiaomi’s kernel sources were made public sometime back.Source]