I think one area where DOW3 really stumbles is teaching new players how to play. Most of us agree that the campaign isn't great and I don't think it's a good tutorial either. Skirmish is all new players have if they want to learn without diving right into MP. Even then, PC mode adds a meta game on top of the other systems that new players are expected to learn. That's a hell of a learning curve.
Multiplayer is where DOW3 shines. What can Relic do in the future to ease the learning curve and get new people playing MP?