Jeffrey Rosen has some good stuff to say about this in his book The Unwanted Gaze. One of his defenses of the right to privacy is that new ideas often seem wrong at first, especially when they're still only half baked. And because of this, progress is seriously impeded when the government has the ability to go through our journals and sketchbooks at any time. This is especially true in our made-for-TV society where most people won't put more than thirty seconds into trying to understand something, esp. considering the factors PG mentions. He suggests that for these reasons innovation may not be possible in a fully transparent society.
I've put the book on my list.