But Google would be really, incredibly stupid to do that. The Reader outrage will seem tiny compared to the outrage they will get if they mess with CyanogenMod, who's used by the most core users of Android, and most vocal ones in the Android community.
CyanogenMod also has a lot of good will with those users, while Google's good will is diminishing by the day. Jeff Jarvis said recently that Google has only done well when it has done stuff for the users, not against them. If I were Google's CEO I would imprint that in my brain before doing something really stupid in the future.
In all honesty, I do not think that Cyanogenmod is used by any more than a statistical blip of users, when the whole of Android is considered. I really doubt Google cares very much about these custom ROMs, and won't start caring until everyone starts flashing them on their phones. Which will not happen any time soon.