Interesting but not surprising. It's just another partnership/JV that's gone the way of many partnerships/JVs: one side uses the other and then unceremoniously dumps them.This provides some insight to their relationship...
http://www.androidpolice.com/2014/1...-ended-poorly-cyanogen-ceo-is-kind-of-a-jerk/
More fool Pei for being 'blindsided'. Business is business, use or be used, and so on.
Fortunately, the OPO will not be short of ROMs in the future.