If anything, Motorola is a long term strategy that just hasn't come to fruition yet. I think we are going to see multiple devices coming from Moto soon......but I think they will continue to keep the Nexus line separate.
Nexus will continue to be reserved for a pure Android experience, but Moto will act as the showcase for additional Android software optimization....
I think they might use a more low-key approach with Motorola. I think Motorola might try and phase out of carrier exclusives and focus solely on perhaps two yearly models, though they might continue to sell the Moto X after releasing the Moto X-2. The writing is on the wall - it's far better, for everyone, for the manufacturers to support maybe two or three actual phones at most. Of course there are the minor variations for regional differences, but it helps make development and support easier, and helps them focus on building a better product with better software.
I think the Moto strategy, for Google, is to play the Pure Android route. I think they will probably continue to let Motorola offer the manufacturer exclusive feature (the always listening low-power cores - terrific battery life, yet it's so easy to activate more often than not I didn't purposefully wake it.
My hunch: it's about demonstrating the quality of Android with as minimal additions as possible, while demonstrating the ways a manufacturer can still differentiate.
It's also, more than anything else, all about some active investment legwork. They bought Motorola, and it's been costing Google - now it's about getting some money out of that investment. How? Motorola was flailing a little bit due to a lack of direction, even though they had significant hardware potential and expertise, and they still seem to have the best cellular radios. So now, they have direction and a focus, and a desire to carve a heck of a lot more of that market share for itself.
I think Google is still trying very hard to give no favoritism to the Nexus program. They have been in bed with LG and Asus for recent years, but they've said it's an open program based on who wants to work with what.
It's quite likely it might still be too early for a Motorola nexus. Perhaps next year, because they've only just gotten a phone that was entirely the work of "the new Motorola" onto the market, since the product development cycle is typically two years. Maybe they've got some prototypes for the next one in the works. I'd love to see that, for sure.