I'm really hoping they include 802.11ac because I picked up an Asus 802.11ac router late last year and I'm all set. I already use Time Machine over WiFi and it would work a lot faster over ac.
And obviously I'm picking up a new rMBP when they release em.
Yes you have a ac router but what about your internet? you have to have an internet and a router to see the difference. One without other don't work