honestman - 3:35 pm on Jan 30, 2010 (gmt 0)
There is another use of rel-"nofollow" which seems problematic. Google and others recommend it to indicate that the site you are linking to is a paying link. If your use rel="nofollow" for such links to external sites--as do I--will having many such legit customers look "unnatural?" I have not seen evidence of this thus far, but I am not clear on how this is interpreted, after all, having many customers is normally a good sign for an authority site when combined with or without non-paying customers.