For me I will still shoot in colour, then convert to B&W using a photo editing program. You will have more "image info" to work with, and have much more flexibilty. At least you can use back the original colour photo if you suddenly wish to.
Another advantage of shooting in colour is you can easily simulate colour filters in your photo editing program when converting to B&W.
Also another thing to note is that your camera sensor will still capture the image in colour 1st, before converting to B&W. The camera's conversion process may not be what you desire.