I had to lookup skydrive to find out what it was. DropBox is known, skydrive isn't. Even though it is a Microsoft product that doesn't guarantee success. What's the user experience? How is it growing? Are people recommending it?

You're right, competition does matter. It matters because it pushes people to constantly create improvements and better products.

However, the point of the article is to not fear competition to the point where you don't take action.