Alright, from what I can tell-there is a reason that Ko-Koro, Onu-Koro and Le-Koro are not featured in the MoL movie. Maybe they were left free so that Bionicle.com and the Comic could still function during the movie-I don't know. I do know at a guess that the only rahkshi to be seen in MoL will be the blue, brown and red ones (that makes it easier for people who don't know their names)
At the end of the trailer it shows t figures zooming past a tower, then a third destroying that tower. My bet is that the third figure is the blue rahkshi who has the powers of destroying buildings with its staff. Also, I found it strange that Takanuva was not featured in the trailer-maybe he/she does not come until after the movie, or he/she appears near the END of the movie and defeats Makuta. Somehow, the slogan "search for the 7th toa" must fit somewhere into the storyline around the MoL movie.
Don't get the idea that Kopaka, Lewa and Onua are dead-the trailer says "Protected by SIX heroes". They are just not the focus of the movie. Maybe Mata-Nui's protectors have split into two groups to better protect their island. And I bet that the Nuva Kaita is only possible within the Kini-Nui.
All in all, I think the movie will be great! Post your own comments/theories here