I’ve done a bit of work with the NoIR Camera, and it isn’t what you’d really expect from “night-vision” cameras, although it definitely gets the job done!
During daylight, the NoIR camera has a slight purple hue from the IR light it receives, so things like trees etc seem a little odd, but nothing too detrimental to the image content.
You will also most likely want a few IR LEDs in there somewhere to provide an Infra-red light source during the night, since the amount of IR emitted by objects naturally is minute in comparison to an LED.
Here’s an example of the different views from the two cameras during daytime (thanks to http://raspi.tv/2013/pinoir-whats-it-for-comparison-of-raspicam-and-pi-noir-output-in-daylight):
You could also always use something like a USB webcam, which has the advantage of a built in microphone, though you wouldn’t have the NoIR capability.
Hope this helps! :)