Making a photo pop in only black in white is fantastic when successful, but that is far from always the case. Choosing only one or a couple of colours to remain in the picture is one of my favourite ways to edit. It gives so much to the picture, and can brighten up even a photo that was pretty dull to start with.
I just edited this picture of my cat Mila. The editing in Photoshop (CS5) took me no more than 15 minutes. If you want to try it I think the video below shows the process well. It is only two minutes long and it is so easy!