"Blurring" typically refers to the "whittling away" of distinctiveness caused by the unauthorized use of a mark on dissimilar products. Anti-dilution protection extends beyond similar products by protecting against blurring and tarnishment.
What constitutes a "whittling away" of distinctiveness is roughly akin to the infringement analysis, namely, the degree of similarity of the marks in question is a primary factor, except that the products are unrelated. By contrast, trademark infringement requires a finding of product relatedness.
