I will say that NATAL has more power then PSEye, and has more more possiblites then Gem.

The only real downside is, that NATAL seems far to futuristic, even for our time, which may or may not click well with the general public.

but overall i say NATAL has more to offer then both the Gem and PSEye in the end.

as we have found out power means nothing this gen just look at the wii, What more does it have to offer than the PS eye really at the moment?

A more noticable problem is peoples reluctance to move forward because of previous experiences.  I've seen the old camera motion control solutions over the years and they pretty much all sucked but I believe this is because they were poorly implemented due to so many factors and not because they were camera or controller-less.  With that said I also believe a controller would be required to adapt camera motion control to existing conceptual presentations of existing games and genres. 

Some inherent problems of the past (in no particular order.  sorry for any dups): 
- different time period where motion control solutions were not widely accepted
- camera resolutions were not good enough in the past
- lighting was always a problem for old camera solutions
- most cameras used RGB and not combination solutions like RGB+IR
- main console processor had to do all video processing and for complex solutions could just not handle the processing at all
- custom development required for every solution by each developer.
- no common APIs made available for all developers.
- mostly only first party developers used video motion capture
- not adapted as a standard
- not enough degrees of freedom to produce diverse solutions that users would feel comfortable with
- 46 point skeletal tracking was not managed * 4 players at the same time
- not enough functionality easily available for use
- not fully integrated into any console interface
- voice recognition wasn't really an option
- multi-player at the same time was not offered or didn't work
- solid facial recognition wasn't easy or used and not integrated into a console os
- all camera motion control solutions required you to stand and not be able to sit (with the exception of EyePet I suppose as they force you to sit on the floor).

Attempts at most if not all of the above points have been designed over the years but not provided in a single device.  Perhaps a single solution will be able to addressed most if not all of the above issues thus allowing a workable solution to be presented.

With Natal as a foundation/standard the idea of other additional motion control devices layered on top is exciting.  Even before Natal was presended at E3 there were other companies working on hand held motion wands for the 360 so perhaps they will come in time as well.

"1:1 control without any lag".  This is absolutely not true.  From watching the Wand videos there is very noticable lag, similar to Natal, and always will be.  The reason most don't notice it is because rairly is the user shown moving in front of the TV with the image.  Most footage shows the user in/overlayed in the TV image but if you find the clips of the user moving in front of the TV and you will see the "LAG".

Wii games are gonna be ported to the PS3 wand.
thats why there are less exclusives for the wand.

Natal's firmware code and research were done and gathered from many different sectors of MS. It is almost like Natal is a patchwork of various R&D that has been going on at MS for years. Trying to attach a cost to this development to Natal alone would be erroneous.

I thought I already discussed how the EyeToy's motion detection via RGB color values was inferior to Natal's methods. This was backed up by a Sony engineer stating the same thing in a video. This is also why the wands are necessary. I really don't think there is even an argument to be had about this. A discussion could be had about PSEye+Gem and Natal, but PSEye alone is really no argument.

And yes, facial and vocal recognition is a software solution. And it appears that it is a solution that Natal's firmware will be handling. This allows for developers to more easily add Natal capabilities to their game. A developer can code a game to work with either Natal or a controller and not have to be limited by the former. For example, if the camera data was to be processed by the console's CPU/GPU, the game's other areas: graphics, sound, AI, etc, are affected by this even though the user might not even have the camera hardware. If it was developed with peak CPU/GPU usage when using a controller, when a user uses the camera, the frame rate will take a hit unless the game was developed where a degrading of other areas was performed. I don't think I explained this very well.

Perhaps a detailed example of this will be more effective. I will use, as an example, the Geometry Wars port using Natal. This game could be played with either the controller or Natal(and no, I don't think Natal is a good fit for GW, but for the sake of examples, I will use it).

//Publicized indexes of the hands.
static final byte rightHandIndex = 12;
static final byte leftHandIndex = 24;
static final byte chestIndex = 6;

private void calculatePlayerActions(byte playerIndex, boolean usingNatal)
{
vector3 acceleration;
vector3 turretVector;
if(usingNatal)
{
//For this particular frame, Natal has already sent the player skeletal data
//to the 360.
Vector3 rightHand = playerSkeletons[playerIndex].getSkeletonPoint(rightHandIndex);
Vector3 leftHand = playerSkeletons[playerIndex].getSkeletonPoint(leftHandIndex);
Vector3 chestPosition = playerSkeletons[playerIndex].getSkeletonPoint(chestIndex);

//initialize turretVector using the unit vector perpendiculer to the vector (rightHand - leftHand)
//initialize acceleration using the hands and chest positions.
}
else
{
//Initialize acceleration by using the information about the left thumb stick.
//Initialize turretVector by using the information about the right thumb stick.
}
}

I know the two vectors that are being initialized are never used for anything in this example. It is just an example of a possible scenario.

Not much, if any, differences between performance of either using the controller or Natal. If the calculations were not done on Natal and were done via the CPU. The first call to getSkeletonPoint would have a rather large overhead as it would start the calculations of the skeletal system provided by the API(ie, developers don't need to code this, MS did the work for them). This allows for some possible retrofitting of games using Natal. Sure, games being retrofitted for Natal will most likely not be as good as one designed from the ground up to use Natal, the option to tack on Natal functionality is there. Facial recognition and vocal recognition directly apply with the example as well.

Using the PSEye for this same scheme would require even more performance issues and a possible failure to determine the depth differences between the hands and the chest due to RGB processing lacking in this department. The developers might even have to code the detection algorithms themselves if Sony does not provide them with PSEye, which is a double hit. Coding and testing necessary for the detection algorithms and the performance hit from using them.

IMVHO experimenting makes sense for both, otherwise Nintendo could leave them too much behind. But then it would be sensible to not expect too much this gen, and anything more than predicted will be welcome. MS lets the hype skyrocket, but there are too many hurdles on Natal's road this gen, next gen it will do much better, if it will be in XB720 standard equipment.

Notice that MS doesn't own TOF camera technology, but only the peculiar way it's used in Natal, so both Nintendo and Sony will be able and free to use it in their future systems, paying tech owners, obviously, but not MS, and this raises an interesting question: will MS pave TOF cameras' way at its own expenses with Natal just like Sony did for BD with PS3?

Whether it's different or not I think the fact that so many PS fans are in here in defensive mode and the fact that the dil...wand only gets talked about even by them in a Natal thread speaks volumes.
Criticise MS for hype (something that has saved the ps3) but if no-ones talking about your product no-one will by it. Bye bye the chance to recoup R&D cost, manufacturing, advertising etc.

no, natal has better tech

Natal has more eyes... So it could be an arachnid.

Nobody here really knows the answer at this point, lets wait for more info, before we go running off half-cocked