Oh, dear. You poor poor silly people.
It is quite clear that Ron and Hermione will end up together. Anyone who has read the book and has half a working brain would know this. I find it rather annoying when people who have seen the movie but not read the books assume that Hermione and Harry have a thing for each other. So I will tell you what you're really seeing. It's not about WHY Hermione hugged Harry, it's about why she DIDN'T hug Ron. He clearly wants her. And Hermione knows that Ron wants her. And Harry knows that Ron wants her.
Read the books people. If you still don't believe me- get an intelligent person around you to read them.
Oh, and to the people that think Harry and Ginny should get together- HURRAH to you! I would love that aswell. But I don't think Harry will be with anyone for obvious reasons.