I would like to be counted as one of those that prefers the "official" and
official start of the next decade, century, and millenium on Jan. 1, 2001
because I like accuracy.  It's just a simple matter of applied mathematics -
a decade = 10 years, a century = 100 years, and a millineum = 1000 years.
Draw your line anywhere in eternity and start counting.  Start with 0, 1,
22, or any number you like to start it with, use binary, octal, or
hexadecimal if you prefer a different base.  You will still need 1000 years
for each millineum, 100 years for each century, and 10 years for each
decade.  In this particular case, someone(s) decided on a particular point
in history, no matter their reasoning or the accuracy thereof, and here we
are at the start of the last year of the 2nd millenium A.D. (2000) and
moving toward the first year of the 3rd millineum A.D (2001).  Both
perfectly good reasons for a celebration.  Of course, I celebrated the
winter solstice - the end of one solar year and the beginning of the next,
it's much easier to understand than any of this other nonsense.

Tally Ho!

Jeanne