The US continues to directly aide Pakistan's flood victims (and, by the way, is expanding the operation), just as UN officials decry the rest of the world for not helping more.
It's a crucial part of the fight against the AfPak Taliban. With the Pakistani government struggling on its own to send aide, the Taliban might well be the primary provider of aide were it not for the US intervention.
Now, many northwestern Pakistanis are seeing US troops and Pakistani government officials / Army troops distributing aid and rescuing flood victims. It's going to have huge PR impact, and reduce the legitimacy of the Taliban, and win more "swing voters" over to the pro-Government side.
It'll also help perceptions of the US, which will make it much, much easier for Washington and Islamabad to work together against the Taliban in the future.