lelouch definitley died at the end, the fact that he died made me cry my eyes out. CC didnt switch, lelouch had to do this one thing for himself.
Tho some theories discuss that, like CC, Lelouch cannot die. I havent watched this anime for a while but basically he may of got this ability from his father etc. Go onto Youtube and theres some theories that in the ending scene (where CC is lying on a cart of hay) the driver is Lelouch. On the original japaneses version it showed the bottom half of the drivers face, it was Lelouches.
Lelouch did die, it would change the point of Suzaku killing him.
ALSO when Lelouch drops down and infront of Nunally she wouldve known it wasnt Lelouch.
THAT SCENE MADE ME CRY SO MUCH AND IT WAS 3AM.....