The Pakistani floods have given the US army an opportunity to counter the Taliban's influence in the Northwest (and bring increased legitimacy to US operations in the area).
US troops are dropping emergency supplies and evacuating civilians with military helicopters--with Pakistan's blessing.
It's a good PR opportunity, and a great way for the US to work together with the Pakistani Army. Furthermore, it gets US troops in the region--no doubt spies and commandoes have been dropped into the region to learn as much valuable intel as possible.
It's unlikely the US will use the opportunity for any immediate offensive or disruptive operations, but odds are good this opportunity will influence future plans for either US commando/spy forces, or for cooperation with the Pakistani Army against the Taliban.