I personally think Sony saw a gap in the market, we can bring in a Wii like controller and get some Wii users to upgrade NOW, Why you might ask? Because next Nintendo will bring out a Wii HD with wiimote, and then why would you consider moving to a PS3/Xbox (unless there is a specific game). The opportunity would be lost.
My first console this generation was a Wii, I was excited by the idea of a responsive controller that would mimic my every move (like the idea of playing Tennis and the controller really having an impact), only to find that the controller was effectively cheating (flick of the wrist and it does the same). Not only that the graphics/games are subpar to the AAA games of the current HD twins. Now i moved up to the PS3/Xbox. But think about all those other possible users who might also want to upgrade. Sony wanted to get in before the Wii 1.5/2, so then there is at least an excuse to get people to upgrade (however small that group might be).
As far as sales go, I think Kinect will definately sell more initially, only because of the total PR rubbish that MS has sprouted, right from the 2009 E3 show. People (general users) are still saying it will work with eye movement, finger movement, Minority report style movement, which it wont, but the general public dont generally read forums and understand this just isnt possible... the general public are not as tech savy as the rest of us.
Move will be a slow burner and i think will do OK, certainly with those that already have the console, it might convince people to upgrade from the Wii, but i dont expect massive numbers.
Games wise, well Move has the better range of games for the controller, while Kinect only has two games of note, Kinectimals (which does look nice) and Dance Central. Neither are revolutionary (though both look great which is important), but will help sell the console, while the rest is pretty poor from a core gaming point of view (imho). Also i doubt very much that Kinect (in this product release) will be able to do any games for the hardcore gamer.
You also have to consider just because it sells, what happens people buy one or two games, consider it rubbish and doesnt buy any more. Its still a success right because they sold a console? Or is it about the amount of Move/Kinect title sales that matter? or is it how many 3rd parties support it?
So I guess the OP said move will fail, but actually there are a number of levels of failure depending on your point of view. We can wait and see until one sells more than the other, but if thats how you judge failure, then personally i think that is wrong.
On a final note (sorry this is so long :) The comment by one user (sorry cannot recall the name), that if Move sales dont set the world alight would affect 3rd parties, I actually dont think it will. If moves sells in the low millions, but implementing it in your game and only takes a few weeks, seriously, I would implement it, because it might mean a few tens of thousands maybe even 100,000 more sales (who knows). Is 5 weeks work to add support that much effort (and it will be less once you have learnt the libraries from your first implementation). While Kinect is going to be alot harder for 3rd parties to add in a normal game you might be developing.
