Unfortunately, you have to buy the magazine today to get the entire interview. They have only released a snippet of it online to send us into a frenzy of anticipation. What we learn from this sneak peek is that the Northrend PvP zone, Lake Wintergrasp, will be about the size of Westfall and will be all PvP. No PvE objectives in it at all. It will also be a static zone, not instanced. He also mentions that it will have destructible buildings and siege weapons, which we knew from his Leipzig interviews. Not much new there other than the size comparison to Westfall.
Kaplan also talked about learning from the Hellfire Peninsula experience. This entry point into the first expansion wasn't epic enough. The design team wants to raise the bar for Northrend. We know from earlier interviews that entry into the expansion will be split. The Alliance will grab their sword and the Horde will get their own damn battlecry and both head into either Howling Fjord or Borean Tundra. How Blizzard is going to raise the bar is still a mystery.
Argh! More infoz, please! If anyone gets their hands on the magazine, send us a tip with details. We'll happily give you credit.
EDIT: Clarified entry points for both factions.
[via World of Raids]