"To date Google has been compensating for the awkwardness of the PC SERP on smartphones with voice search and other marginal “fixes.” Today it took a potentially major step toward offering a distinct search experience designed specifically for mobile that may bury the “old” mobile SERP."
Hmmmm... "Siri-like Spoken Search Results"? The motivation for that seems pretty transparent at first glance, doesn't it.
At the same time, the news was "Buried among the sexy hardware announcements and hair-raising Google Glass demo..." so it's not something they want to crow too loudly about right now. Probably considered a beta release or something like that, at any rate.