Consider a service competing with Youtube; will they have the same streaming performance when delivered over Google's fiber as Youtube? It might even just be accidental (say, Google colocates it's services with its fiber infrastructure) - but it could easily give competitors a big disadvantage if they can't get access to the same performance as Youtube has.
This is actually the defense Comcast is using with their IPTV services. They don't have to pay anything to move that data over public lines, so they don't "charge" extra for it (by "charge", I mean putting it against the caps they recently removed). On the other hand, Netflix et al does go across public lines that Comcast does have to pay for, and they do "charge" for that because they themselves are being charged for it.
Local CDNs are troublesome when it comes to the difference between WAN and last-mile prices for content providers/deliverers.
I want fast fiber. I also want to avoid another evil monopoly from taking over the computing landscape. I miss the old, trustworthy, don't-be-evil Google.
It'll be interesting to see if the announcement addresses your concerns.