Is this "old" times stuff. Certainly not. Reworking a digital picture to B&W can have a hughe effect on the dramatic or documentary side of a shot.
Some things just look better in black & white.
But, a picture converted to black & white from a digital colour shot looks mostly flat,
sometimes like a high quality shot made with a Hasselblad or Bronica mid-format camera
on a very low grain film like a Illford FP 4.
This again removes the dramatic side of a shot and is unwanted unless you want to make a 6 x 3 feet print.
In digital we have the opportunity to rework and select and change the film effect we need
at any time without the need to buy different brands and qualities of films.
But, doing a good conversion to black & white is somewhat tricky and needs just
a bit of aknowledge in a correct use of Photoshop and/or Photoshop Plug-ins.
On this gallery I tell you more about this : http://www.pbase.com/lou_giroud/bw