Indeed...seems very death note-ish where Lelouch somehow got himself memory wiped probably through C.C or through self-geass because the authorities were suspecting him. He lays low while C.C goes and reorganise the remnants of the Black Knights. And Rollo is probably also part of the plans.
Some points to mention: (and yes i prefer to keep spoiler tags until at least a week after broadcast)
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*The black knightmare frame gets a beating....again...kesian.
*Kallen is so hot....and she keeps her Knightmare Frame
USB Drive key in her cleavage.

*Split second nekkid C.C

*Lolis are planning to take over the world. Apparently this is Tian Zhe (Sora?) based on the chinese Kanji.
Kaguya knows her, and she's the current empress of China.

QUOTE
I still want to know when did the black knights know Zero = lulu, while the ones that has been caught don,t
Well...i think its pretty obvious C.C and the remnants planned this out from the beginning and to regain the remaining rebels' trust after Lelouch turn tailed on them, he unmasked himself. Obviously those that got captured won't know this.