All facts taken into account, this is what I think will be the case:
> Google will continue operating as an open source OS, mainly because $$$$$$
> With Motorola, it will give Google a chance to potentially clean up their Nexus brand as a unified experience. They started the Nexus brand to try and go directly to the customer. They got rid of that model (due to it bombing) and are now moving toward a unified experience (much like the iPhone). They have made that clear with ICS (UI redo and consistent programming like swipe left to close, etc) and their recommended font/art/development packages.
> Google will continue to push for Android with third party manufacturers, because they will still profit heavily from this and because the highest selling Android phone is made by a 3rd Party Manufacturer (Samsung). Note: All Android phones are 3rd Party, but I mean relative to "their" Nexus brand.
> Google will also use Motorola phones to push their Google+ centric mentality.
Any other theory about closing the source on Android or the idea that all future Android phones will be made exclusively by Motorola is not business smart. They aren't a billion dollar company for no reason. Any of those silly theories means less dollars and unhappy clients. Let's be real.
BTW you can't use hearsay (explicitly labeled as "Rumor") and claim it as proof, for the record.
HTC One (M8)
Proud Android user since 2007 (G1)!
Past Devices: HTC Wing(MDA), G1, Mytouch 3G/4G, iPhone 3G/3GS, MyTouch 3G Slide, HTC HD2, BB 9100, LG G2x, Sensation, Samsung Galaxy S III, Note 2, Samsung Galaxy S II, Note 3