Ken Akamatsu, the creator of the harem manga Love Hina and Negima, has looked at the research and declares that both moe and harem manga have had their day. Sankaku Complex (warning: NSFW) translates his comments from his blog:

Certainly, the moe boom is finished, and from last year on I think we’re seeing the following phenomena:

1. Male protagonists are absent

Many anime are now nothing but girls, and the role of the “male character being excited by female characters for viewers to empathise with” has disappeared.

2. Male buying power has reduced

Now women buyers of both anime and manga are predominant. Oricon comic rankings show most of the top titles are women-oriented.

3. Male viewers can now empathise with female characters

The number of male fans who simply don’t view female characters as objects of sexual desire at all is increasing, even in titles like “K-ON!”. No more are they just thinking “I want to be part of that circle,” now they are getting into the characters themselves.

Akamatsu speculates briefly that yuri (romances between two women) will be the Next Big Thing (which would be excellent news for Erica Friedman) but dismisses that notion. On the other hand, it could be that the more mainstream shonen publications are acknowledging that they have a lot of female readers and are tailoring their content accordingly. (Shonen Jump was accused of making its characters more slashable a few years ago for just this reason.) The real question is whether there is still a demand for moe and harem manga; if there is (and I suspect the answer is yes) then most likely some magazine will spring up to serve that market, even if the more mainstream magazines shy away.