The ability to use an existing Sprint phone number as a Google Voice number, with unified voice mail, is not a “full” implementation of unified communications. but it offers a feature that always has been a main attraction of unified communications and fixed-mobile convergence.
If you look across the range of specific applications that routinely are touted as UC advantages, you’ll discover that many of the values now can be satisfied, albeit on a sort of case by case basis, and not as “unified” as a full-blown UC solution can provide.
Still, UC seems to be viewed differently than it used to. “Collaboration” sometimes is satisfied, in large part, by social networks of one sort or another, video conferencing or even some aspects of location features.