The first part of this video is actually pretty funny because Pat Robertson is prone to say some outlandish things, and I am not a fan of his in anyway. It is the last part of the video, where Stephen Colbert mocks prayer, that that I take issue with.
Clearly Colbert has not thought about prayer in any substantive way. Even if future events are known to God, it is our attitude and response to those events that are important. Prayer plays a critical role in helping to shape how we respond the daily events in our lives. To claim as Colbert does that prayer is essentially useless reflects his ignorance of it.