This one actually mentions first and foremost, the always-available access to the Net wherever you are and at any time (unless you're in some remote area).
And even Jeff Bezos didn't say that -- something people would understand.
Instead, he said it had a really good radio modem. The implications of that will be understood by about 1% of those who hear it.
That kind of always available and free access is worth $40 to $60++ a month on phones that access the Net. That's why the $359 for the unit. And the Sonys don't have that. At best they will have WiFi which means one has to find a Hotspot somewhere and hope that it's free.
On almost every single column I've read, they never point to this 24/7 wireless access. Pogue did in the NYTimes article today, but it was still a bit subtle. And he forgot it when talking about the price.
Since I am a web-browsing fool, it is used often by me, especially when out of the house.