LELOUCH IS STILL ALIVE

He has Charles' Code which he received when the man choked him. The Code activates first when you die, which happened. And before you say can't have Code and a Geass at the same time, the Code wasn't the one C.C. had, meaning that Lelouch was the first one to achieve Code Geass. He's now travelling the country-side with C.C., living as immortals.

That's the only reason for C.C. to be suddenly so happy again. Also, before you say that C.C. was just talking to the dead like with Marianne, that's not true. She could only talk to her because of the nature of her Geass which allowed her to implant herself into the "hearts" of others. That's how she was able to talk with Marianne. Lelouch's Geass was entirely different, meaning that she could only have spoken to him if he was there.

Also, the screenie of the cart driver who is masking his features competely supports this.

What further supports this is that Nunnally got Lelouch's memories when she touched her, just like Lelouch did when he touched C.C. back in Narita. The only way this could have happened is his Code activating. This pretty much confirms that he has the Code and is alive.

C.C.'s words in the end translated: "Geass is the power of kings, it will isolate you... well, I guess thats a little wrong... eh, Lelouch"

First of all, for all of you saying that you've found information on websites from the authors saying something or rather, please post a link to an ACTUAL DATA-BASED WEBSITES.
Any website with the word 'wiki' in it, means that anybody on the planet can put whatever the hell they want onto it.
That information is probably fake.

ALSO
Lelouch is dead. If he was alive, he would have simply started healing in the middle of that huge crowd. He didn't give Geass to Suzaku, or we would have seen that trippy scene where their minds merge.
When Suzaku said "I accept"
it meant he accepted his fate of being Zero, only Zero, and leaving his old self behind. It had nothing to do with Geass.

When C.C. was "talking" to Lelouch, it didn't mean he was there in telepathy or in actuality.
In Japanese culture, it is common to speak aloud to close friends and family that's dead.
Like in certain anime's where children speak to their dead parents (Ouran Host Club, anyone?)

Also, he did not recieve Charles' code, because to take the Code it is not simply being choked by someone- Lelouch would have had to personally TAKEN IT from him. Charles' and Marianne's codes were simply lost into C's world.

Honestly, I don't know why everyone wants Lelouch to be alive so badly.
The ending that CLAMP gave Code Geass was beautiful and poetic, and it keeps well to Lelouch's character.
For a hero to give up his life it shows the ultimate self-sacrifice- and Lelouch was willing to give up everything and anything for his sister Nunally. It was a beautiful ending, and to keep him alive for another season would just be pushing it a bit.