As much as I hate to say it, I would go so far as to say I see the Google acquisition making it far LESS likely that we will see a Moto Nexus.
The whole business model for Android is essentially the same as Microsoft drove to dominate the PC market. They focus on software and allow other companies to compete and innovate with the hardware and end user capabilities. They didn't buy Moto to make better phones. They bought Moto because they needed the patents to defend themselves against Apple. I could easily see them selling off the hardware unit after raiding the intellectual property vault - and that might be our best shot at seeing a Moto Nexus.
So long as Google owns Moto, they don't want to give even a whiff of favoritism because they don't want the other manufacturers to feel as if they are playing against a dealer with a stacked deck and his own hand in play. Those device makers are the key to their strategy and the key to their success. Google would rather shut down the whole phone operation at Moto than risk defections from the rest of the device makers. So if anything, I bet Moto will get less favoritism instead of more as executives go out of their way to avoid even the appearance of favoritism.