First of all, whether or not some people think that Steinberg are wasting R & D resources on what they may regard as a gimmick, I think Steinberg are actually being quite canny and forward thinking by doing this.
Apple have just announced their purchase of PrimeSense the motion tracking company, and will no doubt be integrating it into future products. Therefore it is only a matter of time before we see this as standard within the next year or so - probably built into laptops etc - just the way we have seen voice control do. So Cubase getting a head start on development for this now, and in terms of how the UI will be integrated, is actually the right way to go.
Very good business sense, and exciting too.
Regarding whether to get Leap motion or Senz, there is obviously the cost difference between the two, but also I am wondering if anyone has any experience of real world usage in terms of how much does one have to use motions which are at a specific angle to the computer screen. I would rather buy the one which is less restrictive in terms of having to be so angle specific, as for me the beauty of something like this would be to use it when you're sitting back in your chair thinking about a lyric or something, and then you want to 'gesture / press play' but if you have to lean forward to put your hand right over the leap motion for example then that kind of defeats the purpose of ease of use.
I also have seen some of the other software apps for LM and they seem cool - like controlling the Mac for general purposes, however if because the Senz being positioned on top of the screen means that you have more of 'an area' to work with when gesturing so less restrictive then I'd probably favour that one. (Even though I hate the idea of attaching anything on to my amazing new apple retina mac book of fear of scratching it ha!