Naruto comes home half a foot taller; this tells him he has changed. But his favorite spot is still on top of the telephone pole, because he can see most of Konoha from there. His favorite food is still cheap, unhealthy ramen—though he has eaten it less and less in the past thirty months—mainly because it is cheap and unhealthy. His favorite colors are still blue and orange. If his clothes aren't as loud, well, they're still loud. He is still going to become Hokage; he keeps all his promises. His confidence satisfies himself.
Sakura watches Naruto realize their approach, sees his grin widen infectiously before he leaps down (the movements somehow more refined, yet just as flashily arrogant as before). He seems different. I should hope so. She finds the possibility strangely appealing—hey! newly cute ass—and perturbing simultaneously. She studiously ignores the gaping absence that has nothing to do with neither her nor him. And yet, you're using double negatives. Konohamaru is bragging. Honestly, she huffs, why waste the chakra on such a childish technique? It's crass, perverted, pointless… Naruto really shouldn't—well, isn't that a pleasant surprise…!—encourage him. Of course, appearances aside, Naruto hasn't changed at all. He still needs a good ass-kicking on a regular basis. It builds character. No, she didn't pick that philosophy up from anyone else. Or, you don't think so.
Sakura's looking at him a little oddly, and yeah, Konohamaru shouldn't have bothered with learning that immature invention of his, but it's flattering. That look is just a little scary, Naruto decides without really deciding. It's the easiest thing in the world to perform the jutsu; easier still to grin and cower like the idiot he is when Sakura balls her hands into fists.