There is a time and place for colour as much as there's a time and place for B&W. Black and white works great if the image has a strong graphical theme or if you are after certain certain dramatic effects. Just B&W for the sake of shooting B&W won't do your images any good. The images posted by Xenedis above are pretty good examples: that sunset looks great in colours but may be lost in B&W. That portrait in B&W uses some dramatic lighting that just may not work that good in colour.

What I'm trying to say is there is no simple reason why B&W photo's would spark less comments than coloured ones. If you find in general you like B&W more than colour, you just may like graphically inspired images over others.