That seems strange to me, since I spend a lot of time on the phone. Reading more closely though, neither is claiming that remote voice communication is dead. What they're trying to say, but can't quite get it, is that the unscheduled phone call is dead. (Voice mail is beyond dead.)
I agree, and Thank Darwin it's gone.
The unschedule phone call was rude. It was almost as rude as having a neighbor walk into your bedroom unannounced. Does anyone of a certain age remember enjoying the sound of a ringing phone (ok, teenage passions excepted)?
We only tolerated it because there were no alternatives.
Now, when we need to talk, we schedule it. My mother knows I phone her daily at a certain time . When Emily and I need to do an impromptu conversation we usually text first to setup the call. At work all my phone calls and conferences are scheduled, even if only by email or IM.
The unscheduled phone call is going away, and the world is a better place without it.
 Via Google voice to Montreal. GV has saved me about $4,000 in phone bills over the past 2-3 years.