On the game's official website, Valve said it wants to "smooth out the traditional launch spike, but at the same time allow anyone to come in and try out Dota 2."
"Dota 2's user base is already larger than any game we've ever made, and it continues to grow," Valve said. "Knowing this launch moment was coming, we've spent the past year working on getting both the backend infrastructure and new user experience into a state where we can welcome in anyone that wants to give the game a try."
The developer said in an announcement that Dota 2's monthly user base is larger than 3 million players, with peak concurrent users surpassing 300,000. Valve says its expanded backend infrastructure is capable of hosting an additional 450,000 concurrent users.
Valve says new players will be added in batches. The developer will open the gates to Dota 2's servers, "monitor how the entire system reacts and make sure that we aren't disrupting the entire community."
Dota 2 is currently available only for Windows PC, but Mac and Linux versions of the game are in testing and will be available "soon."