Valve believes that the solution to the huge barrier to entry is threefold. The first, obvious solution is to have excellent skill-based matchmaking for both individuals and teams. Valve believes that the work going into Steamworks for Dota 2's release meets that requirement. Second, interactive guides will allow players to do more than just read a guide for their favorite hero that has been deemed helpful by the community at large. Valve plans to allow guide-makers to tie their work back into the game by doing things like highlighting suggested item purchases or displaying useful information during a match.
Finally, a coaching system is being deeply integrated into the game. By logging in as a coach, veteran players can do their part to help out newer folks. Valve hasn't entirely decided on the specifics of how newbies and coaches will be matched up, but once they're together a few things happen. The coach sees the pupil's screen, and gets private voice and chat channels to communicate with them. The coach probably won't be able to take control of anything directly (once again, the details are currently under discussion), but information is power in Dota 2 and having a mentor whispering in your ear can make all the difference in the world.
