If any of you saw the HSP episode where Laak and asks for a ruling on whether or not Todd Brunson's forward motion is binding, here is the post on his blog about that incident.
As for WNP, if anyone pulls a stunt like Brunson and does a fake bet with forward motion of your hand but pulls it back, you are going to get a frowny face on your next report card instead of a gold star. Please don't do crap like that. Let this serve as a warning. Oh and by the way, I think the best penalty for doing that in a heads up situation would be that the other player gets to determine if the forward motion is considered a call or a fold. Thank you.