Questions about the new Xbox One Hardware?

[Prototype1864]

Hi guys and girls!,

I watched the reveal and took a look at the spec sheet for the xbox one, i have a few questions i hope some of you techies here can answer,

1, It say's that it has USB3, is it the new standard with the ability to run higher powered devices?

2, Connection is ethernet, but im guessing thats gigabyte and not 100 mb?, and did they choose 802.11n because 802.11ac is not ready yet?

3, i'm surprised they went with 500gb, seeing as 1tb is nearly as cheap i'm guessing it was the keep the price down, hopefully they will upgrade in the years to come?,

4, with the new kinect 2.0, will it be the same as the first with the availability of an sdk for the pc?

sorry if these questions seem really noobish but im asking them anyway ;) i know i don't post often but i'm a reader not a writer ;) and on a separate note i was glad to hear they will support 4k tv's in the future,