I really hope Geass doesn't pull a Wolf's Rain. Maybe Lelouch can be the lonely prince at the end, I don't know.

Maybe Suzaku was mourning for all the people who died, even though it wasn't directly his fault. Or he could have been thinking about the past and what he and Lelouch did, and finally snapped because of all the deaths. Or their broken friendship. Or Nunnally. Who knows. I guess we'll have to wait until the next episode to see how he's doing.

Nice catch on the OP sequence-- I didn't notice the day/night thing at the end. Geass is really getting dark now, isn't it. :/