I was at Google during the Motorola years. There was no integration whatsoever, by design. The Android team bent over backwards not to give Motorola any special access.
I remember reading somewhere that they did not integrate to not alienate other phone manufacturers, they were trying to avoid making the manufacturers feel like second class citizens.
It did. The have a majority of the market. They don't make money selling phones. They make money selling ads. As long as all the phones are using google search and ads they do well.
Simply put so that the oems like Samsung were not allienated into forking Android or going with another OS not that Samsung and Lg didn't try going with another OS.
Presumably to avoid any impression of special collaboration between Google and Motorola that would have spooked the large Android OEMs of the time - Samsung, HTC and LG.
This time will maybe probably actually be different despite Google's short strategic attention span. Seems to me that the main difference between then and now is that Google is probably less concerned about alienating the other Android device OEMs now that Android is more entrenched.
To speculate a little more wildly it's possible Google's motive is also to push the current Android manufacturers to "up their game" in the same way Google Fiber may have been a subtle threat to internet service providers.
also, Samsung has Tizen as a hedge / card against Android; so this may also be Google building up its leverage.
As you suggest, perhaps this iteration of hardware will be like Microsoft Surface. Well built, slightly more pricey hardware that set the bar for the industry..?