B/W for essentials
the world was black and white when I did my first clicks with my father's cam
and it still was for a huge part of daily newspapers when I was a reporter trainee and used a simple own SLR, along with a Leicaflex.
To me BW is basical and essential photography. It will always remain the root of photography as a recognized art because the pioneers worked with those limitations and challenges.
If you don't have other colors than BW, you have to work more abstractly yet effective on your composition. For a BW photo, to be good means really good as to composition, surprise, documentation or sensation. And last not least, BW photography is a damn good training for a graphic way of view.