An update for MacBook Air-like gestures?

MacBook Air Photo

I really liked the demonstration of the multitouch gestures on the MacBook Air during today’s keynote. Its got me wondering though. Couldn’t Apple release an update to Leopard that would enable these trackpad gestures on existing MacBook and MacBook Pro hardware? I think the trackpad on the MacBook Pro is certainly big enough to accommodate most, if not all of them.

I can’t find information on this anywhere. Does this seem like something Apple would do? Or is it strictly a selling point for the MacBook Air? Post your thoughts in the comments.