In an abstract short film, the rapper explores a shinsegae (the Korean term for 'a new world'), full of magical and mystical wonders. At the end, G-Dragon narrates, "Now is the time everything starts anew." You also see Jun Ji Hyun in this commercial, though she is only present in blown up poster-form. I guess this was the Jun Ji Hyun x GD collaboration that entertainment insiders were referring to?
In any case, check out the commercial for yourself!