Dota 2 has been made available to all comers. Have at it: the gates are wide open and waiting on you.
As noted on the Dota 2 blog, the MOBA kept its gated sign-up system while the community grew, until Valve was pretty sure it could handle the pretty amazing numbers Dota 2 pulls.
“Signups are no longer required to access the game, and we encourage everyone to join the 6.5 million active monthly users currently playing Dota 2. If you have a friend who hasn’t tried Dota 2 yet, be sure to take advantage of the new recruitment feature to get additional bonuses for both you and your friend,” Valve wrote.
Dota 2 is available on Linux, Mac and PC. It came out of beta in July. Its invite-only beta was quite popular, although disinterested Steam users complained about the huge number of invites they received, and Valve has been keen to promote recruiting.