My 2 cents guys.
I was listening to a radio talk show yesterday while on this was going on, and they were pretty much covering this story as up to the minute as could be. One caller who called himself a expert ballooner, called into the show said the boy could not be in the balloon as the balloon was too small to even lift the 6 year old. He gave a figure of it taking 8 cubic feet of helium to life 1 pound, and he roughly figured this balloon has enough room for 125 cubic feet of gas. He gave his opinion that the boy was not in the balloon, and he was proved right. If this guy was a so called, self labeled "amateur scientist", if the 20 year ballooning veteran's figures about requiring 8 cubic feet to lift 1 pound are true, you would think this guy (the father) being a "scientist" would have researched enough to know this formula as well. I think he is a media whore just looking for some attention.
Now what makes me think this was all a scam or a attempt to get some publicity is that the boy slipped up in a interview and when his dad asked him why he did not come down out of hiding when they were calling his name, the boy responded to his dad with, "You said we were doing this for the show!". Dad was apparently quite taken aback, and lost his composure. When questioned about asking his boy what he meant with the comment, the father's tone quickly became defensive and he was suddenly outraged at Wolf Blitzer, and was irrate that after all the family had just gone through that they would be questioned about this.