This is potentially huge and disruptive news for the competitive scene. Using Steam's in-game billing DOTA 2 tournament organisers will be given the option to charge users to watch the competition in-game.
As Valve put it, "helping tournaments become more financially stable helps all the players participating in them." The in-game charging is meant to offer tournament viewers an alternative to web-streams, not replace them. As Valve say "we think there are some customers who'd like to invest in a higher fidelity, richer experience."
This isn't the only update coming to DOTA. Teams will now be able to brand themselves in-game with logos, and retain stats on their long term performance. The in-game viewer will also track competitive matches and highlight them to viewers.
There will also be a team-matchmaking pool, allowing for teams to play public competitive matches outside of tournaments.
The first tournament to use the new payment methods will be the Defense. It's a massive moment for e-Sports - a game client offering community organisers the chance to directly bill viewers. Valve are moving very, very fast to bring financial support to what can be an extremely unstable industry. You've got to applaud what they're doing.
If I was organising a tournament, I'd try and tie up a deal where some Dota 2 items were offered as a sweetner for a ticket purchase.
Now; let's see how Blizzard respond in Starcraft 2.