*snort* Good luck, Japan. If the US has failed to crack down on illegal distributions and sales of its software and movies in countries like China, what makes Japan think the US will have any sucess in this area?
In my opinion, Japan is merely acting on complaints from animation studies. This is how it responds - by sending a polite letter to the US government to voice its complaint.
But unless Japan wants to spend billions of dollars cracking down on this problem, I don't see any point in the action other than a nice gesture to the industry. There will always be ways for fans to obtain anime - whether that's on online video sharing sites, auctions(buy a poster, get the series for free!) or by smuggling the product out of the country.
In my opinion, Japan is merely hurting its anime industry through such action - foriegn clients tend to pay big bucks for anime related goods, from cels and sketches, to life sized models(a few Ah my Goddess and Gundam life sizers have sold for about 10K each). The more fans that are conscious of an anime, the higher the liklihood of that anime being licensed in the States. The higher the liklihood of licensing, the higher chance a show has of making a substantial amount of money.
However, unlike other countries, Japan has a strong sense of nationalism when it comes to domestically produced products. Unless you live in Japan, most sellers on Yahoo Japan will not send items to you, even if you can speak and write Japanese fluently. Although these sellers are aware that it will hurt them in their pocketbooks(deputy services generate more sales), many YJ sellers do not care.