Oddly enough, this scene is actually one of my favorite NaruSaku interactions. I feel like both their characters level up there. Sakura is confident in her skills, in her knowledge of Naruto's skills and in her support of him. In that one scene she illustrates the gulf between her and Hinata. Hinata is still holding on to her childish fantasy of Naruto, while Sakura understands exactly who he is and just how powerful he is. And Sakura has no problem correcting Hinata. It's not meanness either — as NH fans love to paint Sakura that way. Instead it's the attitude of a true partner. And Hinata is showing just how far away she is from knowing the real Naruto.
And as if to reinforce all that, in the next panels Naruto explodes out of the water, angry and powerful, proving he isn't taken down so easily. So Naruto's actions verify that Sakura was right, and that they are completely in sync. They don't even look at each other or interact - they just are in sync. This partnership doesn't happen in NH or SS, either before or after.
To me, it's an awesome little NS moment, and Sakura telling off a hand-wringing Hinata is just the icing on the cake.
And it shows Sakura has her priorities straight. While yes, caring about your comrades is important, it's not good if it leaves you open to be killed either. If the others hadn't been there and it was only Naruto and Hinatatas, "Tobi" could have easily taken her lack of attention and used it to kill her with impunity (not that he couldn't do so anyway, but the situation would further justify it).