Валв определились с размером взноса за публикацию игры на Стиме.

Он составит 100 долларов США за каждую игру.
Подробнее можно почитать тут:
So in the end, we've decided we're going to aim for the lowest barrier to developers as possible, with a $100 recoupable publishing fee per game, while at the same time work on features designed to help the Store algorithm become better at helping you sift through games.