Hadn't even played Dota 2 before last week, never watched any before this weekend!
Watched what I could last night. Saw the first two matches and part of the third, enough to see it wouldn't be an Alliance steamroll.
Then had to go to bed....damn work, damn NA time zones....
Watching it really worked for a newbie. The analysis of the picks at the start helped spell out hero strengths, weaknesses and strategies that you could then try and see working during the game. They seemed to be good casters.