An interview about Dota 2 monetization was released by Gabe Newell to Gamasutra at the end of August.

"The primary focus for us at this point is not worrying about monetization, and it's instead worrying about getting the game right," he explained.

"Our focus is really much on building something that's cool, and then we'll worry about monetization. So we're not going to worry about that until later. Premature monetization is the root of all evil," he said.

When asked whether he believed being aware of your monetization design was important during the game design period, Newell responded, "I think not sucking is way more of an important thing to pay attention to first."

"I think every gamer can point to shipping too early, or sucking, as being a way more dominant story in our industry than, 'Oh, it was slightly cumbersome to give the company money.' I mean look at Minecraft, right? Notch wasn't thinking through his incredibly precise monetization strategy."

Nothing has been changed during these months and at this moment is still uncertain what business model Dota 2 will follow when released.

Dota 2 will be Free 2 Play

Gabe Newell, Valve co-founder, announced in an interview published on 20 April 2012, that Dota 2 will be free to play.

"It's going to be free-to-play -- it'll have some twists, but that's the easiest way for people to think about it," Newell said.

Source