Time to geek out, folks! A media magazine, Tsukuru, recently posted a list of the top 15 properties for each of the top three manga publishers: Shueisha, Kodansha, and Shogakukan. It's only for the period from April 2010 to March 2011, i.e. the last year. And it's a very good look at what sells in Japan, and how that doesn't always correspond with what sells in America.
1) One Piece
3) Kimi Ni Todoke
10) New Prince of Tennis
12) Tenjou Tenge
14) Nura: Rise of the Yokai Clan
15) (tie) KochiKame
15) (tie) Mayoi Neko Overrun
15) (tie) Beelzebub
As you can see, Viz are pretty much on the case here. All these are licensed there with the exception of New Prince of Tennis (old one still going); Gantz (Dark Horse has it); KochiKame (169 volumes, unlicensable); and Mayoi Neko Overrun and Beelzebub. Of those last two, MNO is fairly new, and also is a harem comedy, something which doesn't sell as well here as people expect. And Beelzebub has nudity issues, even if it's baby nudity, and is also about delinquents.
As for Gintama, well, what can you do? We don't even know why it's being discontinued here, really. We assume sales, but who knows? Maybe the creator pulled his approval; maybe the translator burned out (it's a notoriously hard series to translate). All you can do is sigh and hope tastes eventually change...
On to Kodansha, which shows the widest variance between Japanese and North American tastes:
1) Nodame Cantabile
3) Saint Young Men
4) Fairy Tail
5) Big Windup!
6) (tie) Billy Bat
6) (tie) Moyashimon
8) (tie) GTO: Shonan 14 Days
8) (tie) Hajime no Ippo
10) Initial D
12) Ahiru no Sora
13) Ace of Diamonds
14) Mahou Sensei Negima!
15) Kindaichi Case Files
...man, if I'm Kodansha USA and I'm reading that list, I'd want to cry. Let's see, hiatus series; owned by Viz; unlicensable; Kodansha USA; sports manga; Urasawa, so who knows?; hiatus series; sequel to out-of-print title; unlicensable sports manga; out of print; owned by Del Rey; sports manga; sports manga; Kodansha USA, and notoriously bad seller cancelled and out of print here. That's 2 proven sellers for the new company in a list of 15. I don't really know what to say, and don't want to turn this into a 'why doesn't sports manga/josei manga/etc. sell' post, so let's move on...
1) Case Closed (Detective Conan)
2) Hayate the Combat Butler
3) Cross Game
5) (tie) Kekkaishi
5) (tie) Kyō, Koi o Hajimemasu
7) Iryu - Team Medical Dragon
9) (tie) Kanojo wa Uso wo Aishisugiteru
9) (tie) Suki Desu Suzuki-kun!!
11) (tie) Rin-Ne
11) (tie) Kenjiro Hata Shoki Sakuhinshu
13) Kenichi the Mightiest Disciple
14) (tie) Bokutachi wa Shitte Shimatta
14) (tie) Dr. Koto Shinryoujo
14) (tie) Gaku
Despite having many titles that make me think "no way are we ever seeing that", this is a more promising list than Kodansha's. 5 of the titles are being released by Viz: Case Closed, Hayate, Cross Game, Kekkaishi, and Rin-Ne; a 6th got a special collector's edition, Oishinbo. Of the rest, Major is a sports manga and is 74 volumes. No. Team Medical Dragon and Dr. Koto are both long medical drama mangas that would do well as a Viz Signature title if Viz Signature titles sold better than they are right now. Kenichi has all sorts of issues, being overly long and unlikely to stop anytime soon. And Gaku is about mountain climbing. Oh yes, and Kenjiro Hata's one-shot collection, which isn't going to come out over here if Hayate doesn't sell better.
That leaves four other titles, all shoujo series. Two run in Cheese! and two in Shoujo Comic, neither of which are what Viz tends to mine for shoujo series (they hit up Betsucomi the most). Kyo Koi wa Hajimemasu in particular was made for the Black Bird crowd. Of the others, Kanojo wa Uso wo Aishisugiteru is about a moody composer and his cute high-school girlfriend who's in a band. Shoujo K-On? Suki Desu Suzuki-kun!! is a complicated romantic manga about a group of people all in love with someone else, and would sell more to the Butterflies Flowers/Ai Ore crowd. It also had an anime. Lastly, we have Bokutachi wa Shitte Shimatta, which again is about a shy girl and a handsome bishonen guy, and is by the author of Kare First Love, which Viz put out a while ago.
So, let's sum up: the series I think will be licensed within the next year or two? New Prince of Tennis, Mayoi Neko Overrun, and two of the four shoujo series from Shogakukan. As for what I'd LIKE to see licensed, regardless of 'sellability'? Saint Young Men and the two medical dramas. Oh yes, and un-hiatusing Nodame and Moyashimon would be nice as well. :)