i prefer black and white for all my photos. b&w just seems to naturally draw your attention to the subject. color, for me anyways, just adds a lot of unnecessary confusion and fights for your attention with the subject. unfortunately, my family doesn't agree with me and i have to take family photos in color.
Black and white introduce another element to a photograph: Abstraction. At the same time it removes other elements tagged to colour photography: time and reality. Thus with black and white I can compose an image that in 100 years will still be of the present and at the same time futuristic while if that same image had been shot in colour it would be outdated. Of course not every subject fits black and white especialy when the main subject of that photo is colours.
black & white for me sometimes is the only way to show the essence of a motif. But sometimes it can also be necessary to reflect the colours to express the essential inner space - it just depends. The most interesting thing is to find out, how to transpose the things into the adequate mood.
Ansel Adams had a lot to say on visualisation in his trilogy books on black and white. When I started I was doing only doing black and white but I had to go colour due to commercial demand. It seems to me that the public lack of the black and white education that was still there prior to digital. The " I want it now" attitude doesn't live much choice for the ones who make all their income from photography. Sorry I got carried away it's probably another topic I'm replying here. I often hear my clients saying: I love black and white when I ask why they are unable to give me an answer.
For me the advantage in making digital photos is, that you got more possibilities in manipulating b&w and at the same time these possibilities are much easier to use - so that is good for acting creatively! But the other thing is: This may be an advantage, but it may be more difficult to work out and make a decision about a special style or language that you commonly try to discover. What I want to say: in the whole it is not easier to make digital b&w, so why say b&w goes down? I mean, it is a challenge, isn't it?
I really like it when I click the "convert to grayscale" check box and turn the objects in the frame to pure forms & shapes. Then playing with the channel mixer makes it more entertaining until you find the correct shades of grey... I agree with Bresson... Photographing forms/shapes is much more easier and entertaining than photographing colors.