In fact EVERY website that uses affiliate link parameters would be affected

e.g. if these 4 urls would be indexed by MSN (or mabye a bit more)

mysite.com/?affil=test1

mysite.com/?affil=test2

mysite.com/?affil=test3

mysite.com/?affil=test4

THEN msn could already remove your site mysite.com from the search results for a duplicate content penalty.

The post also gives some clues about how to get rid of the problem, but this largely depends on what’s going on with the GET parameters… e.g. some affiliate sofware does NOT allow removing these parameters (for obvious reasons of tracking!!)

It’s time for an algo-update for MSN and all webmasters to have a close look at their most valuable sites.