Not forks
The already-popular MIUI rom used in Xiaomi's phone is hardly a fork - even less so than the Motorola and HTC customisations, in that it gets updated within days of any Android release.
The forthcoming Amazon tablet sounds like it might be a real fork, in that it's derived from an earlier Android release and will not provide access to the Android App Market. Everything else, including the Tencent variant which provoked this article, not so much. So, why does it read as if there is a large and growing number of Android forks?