How does this work if the game itself isn't programmed for it?
I personally hate the idea. It says "You will be able to enjoy First-Person Shooters (FPS), or any other game where targeting is important, the way they are meant to be played." A console FPS, with CONSOLE being the key word, is not meant to be played with a mouse/keyboard. If it was it wouldn't be made for a console. It would be a PC game. Odds are if you play console first person shooters you're looking for something different than PC first person shooters. You're willing to sacrifice accuracy in place of an easy-to-use controller. Plus one the advantages of playing a console FPS is that everyone is in the same boat. All you can use are controllers so thus everyone is on a level playing field. If you don't want to use the keyboard/mouse setup in a PC FPS you're f*cked. There's too many people that use it so if you're not comfortable with that setup you're going to lose. On a console that unfair advantage is taken away.
In short consoles provide an alternative way for playing first person shooters. By adding keyboard/mouse support you are removing that alternative. It all becomes the same then if you like it or not.
Plus I don't get why people want to use this setup for console first person shooters. A GOOD console FPS like Goldeneye is designed with the controller in mind. Changing the setup isn't needed because the whole game is designed around the controller. Why do I need more accuracy when the game is designed in such a way that the controller provides all the accuracy I need?
I do think that mouse is a good addition to a console for RTS or tycoon games which are currently not very common on consoles. However I generally feel that PC gaming and console gaming are different for a reason and there's no reason to blur them together. PC gamers like PC games & console gamers like console games. So don't alter console games for PC gamers or PC games for console gamers.