well there certainly is a lot of food for thought----- full of alternate theories

here are some more links with interesting reading

http://genealogy.suite101.com/article.cfm/who_are_the_black_irish_

http://en.wikipedia.org/wiki/Black_Irish

http://www.suite101.com/discussion.cfm/irish_genealogy/45518

http://www.darkfiber.com/blackirish/

Rootsweb has a mailing list devoted to the topic

http://lists.rootsweb.ancestry.com/index/other/Ethnic-Irish/BLACK-IRISH.html