Valve explains 'progress' toward a new Steam Store content policy
From Engadget
As far as the games that are (or will be) allowed, the plan is for developers of games with violent or sexual content to write their own description that includes context of how the material appears.
I may be wrong, but I think Valve will regret this model. It’s built on a principle of having no principles and that’s a hard sell for many parents. I’d never give my kid access to a system like that.