5 overs too short?

The whole Twenty20 concept is about shortening the game to make it more fun for audiences that are new to cricket, as well as existing audiences, and allowing games to be played in the evenings, allowing 9 to 5 workers to go to see some county cricket.

But there's part of me that feels 5 overs each is getting absurd! It's important that Twenty20 finals day offers some excellent AS WELL AS exciting cricket if it's to retain the knowledgable cricket audience. 5 overs each makes matches even more of a lottery which potentially means that the teams in the quarter finals aren't there because they are the best, but have been the luckiest in some absurdely short matches.

If you can't play 10 overs each is there any point in playing at all?