This is where the battle lines are now drawn between Canon and Nikon for sure. Given my 3 year old interest in wildlife I think if it had been 4 years ago and before I got the bug, I'm fairly sure I would have bought the Canon 7D and the 100-400mm IS lens. I would have kept to Nikon for landscape and because of my high investment in pro lenses. The game has begun and we can be sure that both teams will present a APS-C camera which will blow our imaginary socks off. Brinkmanship to the end I'm sure.
Interestingly, I haven't the slightest interest in video and have had my D800 for 9 months and my D7100 for 2 months and even on my D90 or D7000 I have never even switched it on! Perhaps I should before the warranty runs out So that wouldn't be a game changer if I was considering a D400.
It's going to be an interesting and exciting few months for those longing the latest DX semi pro offering.