Not quite not quite...
Sadly, there likely won't ever be an FPS for Kinect. It's just not accurate enough to detect your fingers, hence no trigger. Of course, it does have voice detect, so you could always shout "BANG" or "PEW-PEW-PEW". (If anyone ever does this I may never stop laughing.)
Then there's the aiming. Hold your arms in front of you, as if you were holding an assualt rifle. Now move your front hand left and right WITHOUT moving or re-angling your rear hand. Doesn't make any sense does it? How does the software cope with this, bearing in mind that when pretending to hold a gun, your hands are NEVER in the correct alignment. Much as MS would never admit it, the aiming just wouldn't work properly.
Then there's the other controls. How do you walk, run and strafe? Actually doing so requires far too much space, not to mention the fact the the "world" (i.e. the TV) would then move in the opposite direction. Running on the spot would just be stupid, and doesn't really solve strafing. Remeber, all of the games annouced for Kinect so far are on rails, with good reason.
Lets take another example of "big lad's" games - racing games. I've seen someone else breathlessley imagining the possibilities of Forza with Kinect. I'd be inclined to disagree.
1. You have to stand up, an instant fail for any racing game.
2. There are no sensible controls for the pedals, and no controls for any other actions at all.
3. Most steering wheel and pedal kits fail because they cannot be mounted securely to a surface, making the game VERY hard to control. This obviously suffers from this.
4. The "wheel" is totally weightless, leading to a complete loss of any tactile feedback.
5. You have to spend valuable (for pro racing) brain cycles remembering to keep your hands at a fairly fixed radius, and at an exact 9-3 position.
6. Because of the limitations of the controller, you have a maximum (comfortable) steering lock of 90 degrees, resulting in twitchy, oversensitive controls.. That's right, you need more elbows.
7. It makes you look like a total clunge.
7 was just for fun. But quite seriously, this could easily be the single worst racing control scheme ever, and I don't see the FPS one stacking up any better. And it really does make you look a TOTAL clunge.
For all of MS's waxing lyrical about this being the most revolutionary controller EVA, I really can't see it. It looks fun, for a little while, but I'll be VERY surprised if Kinect ever gets any real adoption, or support. In 12 months time it'll likely be all but forgotten. If MS were a bit more confident of it's sucess, of course, they would charge more like it's market value (about £40, I reckon) and re-coup the money through the high volumne of software sales they will make, right? I mean, it's not like they started to think that no-one would buy any other games for it, and they better grab all the cash up front, right?
Whatever you think about the "Kinect = EyeToy" argument, you can't really argue with the fact that they are setting out to do the same thing. Both intend to let you control a game with your whole body. Sony eventually realised that without buttons you loose direct, instant control, you loose tactile response, and most importantly, you loose the ability to navigate menus sensibly. You talk about gestures, but how long do you really think you'd control your computer by waving your whole arms about like a lunatic? Almost every succesful invention and innovation ever created takes a task, and allows you to do it whilst exerting less physical effort.
This is nothing like the PS3 - it's not at all powerful, or revolutionary, or even new really, (does bolting a couple of over the counter components onto an existing product count as new these days?) but has been put to a reasonably clever use fulfilling a single small niche. In fact the only bit of your comment I do agree with is that it's probably better for doing other things than playing games.
P.S. - I hope I'm wrong, because I care not for silly manafacturer loyalties. If this is good, I'll buy one, no questions. I just can't see how they will overcome such vast and obvious limitations in any kind of sensible fashion.