BIND - how predominant?

[Erik J. Sawyer]

WITHOUT going into a flame war about how BIND is (or isn't) superior to
every other flavor of DNS around....

Can someone point me to an AUTHORITATIVE resource which states the
percentage of DNS servers on the net (or in the public & private world)
which run a flavor of BIND on a flavor of Unix?  I need this info as
research for a presentation.

Much obliged,
Erik J. Sawyer
Senior Consultant
NTP Consulting