There's something about the tension between the characters... I think it's the fact that there's so many things unsaid and hidden that you're get to be really worried about it but without being uncomfortable. Enough intrigue to keep you immersed the entire movie.
Also, there is this scene with the old lady, that was really entertaining and reflective. Hopkins and Pitt make it seem so easy... but I must say Claire Forlani's the one who shines brighter here.

PD. What's their kissing problem?

I had no expectations and I think that made the entire experience even more emotional... I mean, the fish metaphor was mindblowing and the jokes were amazing. I think it's time for us to be less like Joe and more like 22... There's no dream that can come true without action

Great movie... didn't like the Shakira song