I'm also wondering if it's not "less" than a fork, i mean with the new cryengine anouncements, are they still actively getting cry updates or did they fork and have to work alone past that? If the later lumber sounds like a bad deal, specially now that cryengine also is free (pay what you want, including 0, no strings attached).
Question of course is how much resources CryTek has left to improve CryEngine further IF the rumours of their financial troubles is true.
Maybe they struck the deal with Amazon to give CryEngine an overhaul with the money, without mentioning the fact to Amazon? That would be rather cunning of them!
On the other hand, if not the skills and expierience, Amazon would have the money to get lumberyard to where it needs to be to be competitive with Unity and UE4 in the Indie and low budget AA space...
Could turn out to be an interesting arms race between the two of them.