The best use of music in a business
video creates three benefits:

1) The music entertains, and thus
     attracts interest. The viewer
     then becomes more open to
     other elements of the video.

2) The music communicates an
     emotion or symbolism which
     relates to the business-purpose
     of the video.

3) The musical phrases and/or
     rhythm create a framework
     with which the visual images
     can be displayed.

This last point supports the first
point. (and sometimes also the
second point as well) When the
visual transitions correlate to
the music well, it's interesting.
It's also possible to fine-tune
these transitions so that they
relate to the business-purpose
of the video or at least relate
to the visual images. A video
showing an assembly line might
benefit from transitions which
digitally move one image off
screen to display the next image.

The music should be chosen with
the business-purpose in mind. If
that means promoting enthusiasm
for a new product, the music must
convey enthusiasm! But it needs
to do so in a style which relates
reasonably well to all elements.