It isn't often that I disagree with Jakob Nielsen's Alertbox pieces, but his latest seems to me to be somewhat off the mark. Jakob is arguing that the paid advertising of search engines is leaching value out of the sites that pointed to, although he does acknowledge that the user probably wouldn't find them in the first place without the search engine.
However, his analysis and prescription for a solution to the problem he perceives omits one very important point: I return to business sites because of the value I experience as a consumer - I won't return because they e-mail me about offers (in fact I'll unsubscribe from such spam), I won't join loyalty schemes because how often do I need a new freezer for heaven's sake? I'm not going to search a product for the seller's URL - which would probably be stuck in some inaccessible location. I just want value for money.
Good usability design can deliver a lot, but it can't replace consumer value.