There's value in knowing what you want and where you're headed, but as we're reminded in James, our lives "are a mist" and we don't "even know what will happen tomorrow."

I think we need to hold loosely the plans that we make.  It's ok to say, "I don't know," when we're following God.  We don't want to underestimate Him nor do we want to head in the wrong direction.  The important thing is that we let HIM drive.