Disturbing thought number 2. From CEDEC 2010 (31 August - 2 September).
7:50 - Clockwise, from top left: new shader, post-processing, self-shadowing, five idols, 4x multi-sampling anti-aliasing, 60 fps. The caption: To reduce increasing load, all these systems must be redone... and he adds the fact that they scrapped them completely. As an aside, the details will not be in next month's Gemaga, even if they say they're revealing secrets.
9:00 - Pretty much everything changed. I think he says they stopped using the middleware they were using, and data formats for models and such changed around. Some people are saying this is why the game isn't coming out on the PS3, which I think is... not entirely right.
Maezawa: "We couldn't call this Idolmaster 2 if we didn't remake the everything from the ground up!"
http://www.nicovideo.jp/watch/sm11972169 (~9:20)
All those comments that said the complete system overhaul was why the game couldn't be ported to the PS3? ... I hate to be the bearer of bad news, but it could be the exact reason it could be ported instead...
Also, some comments around Nico point to the official page's artwork.
http://www.bandainamcogames.co.jp/cs/list/idolmaster/im2/ps3/They say there's some very suspicious screen real estate not being used right smack dab center of the pic. Nobody's in the center - Ami and Mami are to either side of the center line, and so are Iori and Haruka. It's like you could stick a face right under Haruka's arm...