I remember that vid - it's Radiohead. They do look like P4 figures walking around though there's some kind of funky 3D filter on them that's messing with their polygons. I doubt it was done in poser as the Thom Yorke model looks like some kind of complicated motion-capture effect. They probably just exported the P4 figures after setting up walk cycles etc.

The Radiohead website would probably have the info you're after or link to the director's site.

Cheers