Reading the latest news about Firaxis' XCOM, it doesn't really seam to be a great threat at the moment.
The day the announced the game I thought "Wow! That's it. That's what I've been waiting for". But then during the next week there were quite a few info leaked about their implementation of x-com, and seems like they have dropped too many things that people love original x-com for.
I can't really stand some of the changes:
- only one real base (and if it's only one you can have, then I really doubt they will allow aliens to attack it - otherwise if you're not prepared to defend it's going to be a 'game over'. And seeing their approach for more 'casual' games, they won't allow it.)
- infinite ammo ( for me micromanagement of your bullets and ammo was something important and fun )
- No AP (they've dropped it, and instead will use standard system of 2 actions allowed: 'move + action', 'move + move'... )
And that already is enough to say that XCOM won't be anything close to x-com we know and love.