It's probably due to people checking link popularity for the domain. Link popularity checkers like Marketleap's use "link:harrywang.com" with AltaVista, and AltaVista uses Overture for sponsored links, so that gets counted. Overture considers anything separated by symbols to be separate words and sometimes alphabetizes them, hence the "harrywang.com link" instead of "link:harrywang.com" like you would expect.