Originally Posted by JD 2020

The API will be available for free consumption. It's not about making money. It's about empowering the community with a more open data platform and making it easier to access. Sites like LoLKing and EloBuff have to jump through all sorts of hoops presently to access the data they display, which limits their ability to innovate.

The player behavior team is well aware of toxic matchmaking concerns and can probably speak better to ways they're presently improving the types of things you refer to. These things happen when matchmaking already, and I'm not sure the existence of an API will make them much worse. We'll always have a team dedicated to improving player behavior in-game who will monitor that toxicity, and have given their blessing for such an API.

Personally, I'd rather have a sea of awesome community content with a few bad apples we target and mitigate against, rather than an empty sea of content but with those same bad apples that we target and mitigate against .

-JD
http://twitter.com/JD_2020