This leads to two questions, the first being, "Is the American market of Otaku as easily exploitable?" Being that there are about 30 of these cafes in Tokyo's Akihabara district alone, I'd say they're quite popular, I'm curious if any business minded individuals might be planning something similar in say San Fransisco, Los Angeles, or another city with a heavy Japanese population. Even a city with a large Otaku fan base, such as (apparently) Baltimore, where Otakon is held every year would present a relatively large customer base that would most likely cream their pants at the opportunity. Obviousily, if you look at market trends, it's pretty easy to see that anime sells and that most Otaku are actually pretty blind to the quality of a product provided the product is related to their fandom.
The second question is, "Are Otaku really having this large of an impact on culture?" Obviously there are a lot of considerations to make when asking this question and relating it to the article since the cafes are in Japan, but provided that they are very popular there and could in theory be very popular here, are Otaku now a major part of the 13-18 (And even broader) marketing bracket? I think it'd be worthwhile to investigate how Otaku actually impact the market base of things such as DVDs, video games, etc to see their influence on said areas of popular culture and to made try and grasp the full brevity of the fan base's buying power and their affect on pop culture.