Yes, of course we are under an NDA with Microsoft, but that's not really news, we have been under one since years, well before FSX was released.
From what we know about the new "Flight" title (and it's a lot more than what the community knows) I don't think this will affect much our future developements for FSX.
From now onw, until we get more details from Microsoft about what we can discuss and what we can't, I ask everyone not trying to get any more information from us, other than the official press release.