You do right to borrow one.
I didn't fancy it at all, but was impressed when I borrowed one for a day or two. Would've bought one at that point if it weren't for the fact my front room's a bit too small. The xbox kept trying to get me to move back or sideways slightly, to get into the optimum area, but it just wasn't possible to do so.
Rumours abound that Kinect 2 will have more cameras and therefore be able to track objects much more accurately and in smaller rooms.
Speaking of rumours and the future of Kinect... I read a canny rumour about future generations of Kinect-based gameplay, yesterday. Microsoft apparently have a patent filed for something vaguely akin to a star trek "holodeck". Kinect detects where you are and what you're doing. HDTV shows the main action. Projector fills the rest of the room in with background/peripheral info. AR glasses show virtual/holographic 3d objects within the room. (None of it addresses the issue of the user hitting walls/furniture if they take a few steps in any direction, mind.)
Of course, it's just a patent and the big companies file thousands of them every year with most amounting to nothing. Nice concept though
patentlyapple.com.