Another interview from IGN: http://jp.ign.com/tohotenkusho/19395/news/steamzunproject
This has something a little meatier in that he is basically giving the OK for Touhou fangames to be added to Steam.
Original Interview Text:
――ちなみに東方ProjectのローカルルールにはZunさんがリリースしたプラットフォームでは、二次創作をリリースしても良いというものがありますが、今後、Steamで東方Projectの二次創作がリリースされる可能性はあるのでしょうか。 (もちろん、これはZunさんの意志によるものではないと思いますが。)
たぶん出て来ると思いますよ。そういった事情もありましたよね。Steamで二次創作出したいってう問い合わせも多かったので。それはもう僕が出ていれば問題ないでしょうという流れで、出て来ると思いますよ。
――なるほど、ではあとは各サークルによりますが、出て来る可能性があるということですね。
各サークルの判断によりますね。こちらでは問題ないという形です。
Rough Translation:
Q: There is an insider's rule that one can release Touhou derivative works to the platform as long as ZUN implemented it first. (Now that ZUN implemented Touhou on Steam), is there a possibility on having Touhou derivative works on Steam?
ZUN: I'm sure it can come. Now that I think about it, there were a lot of requests that they wanted to release their derivative works on Steam. Now that I first made my move, I'm sure there's no big problems, is how I think about it.
Q: Then, if there are Touhou dervative circles willing, Steam release is possible?
ZUN: I'll let them decide on that. From my side, there are no problems.
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This also looks like a good read, from thcrap people.
http://thcrap.nmlgc.net/announcements/th16steam.htmlWhat I got out is that Playism's TH14 was sold such that it doesn't run under Western OS environment, and that Steam's TH16 release shouldn't go through the same path.