I'm sure nobody cares, but I was the one who originally posted that screencap in a Livejournal community. It's from the exclusive U2 iPod video "Love U2". I've made other caps of it. I'll post one another one, so at least I can say I contributed something, *LOL*
It's hard to tell, but he was smiling in this part, I assure you! It was just... subtle, haha.