the fourth installment in the core franchise (posted after the break) features no gameplay, but includes a great deal of the chartreuse crystal that the world can't seem to live with (or without). It also features an appearance by bald-headed Nod leader Kane, a possible alliance between two old enemies, and a glowing, swirly ... ball ... thing.
Confused? We're right there with you. Check out the trailer after the break, but brace yourself -- we won't find out what the hell is going on until 2010.