The official guidelines for developers working on 3D titles for the PS3 recommend that studios avoid trying to make their 3D games support 1080p, instead suggesting that they stick to the less demanding 720p resolution.
A true 1080p image consists of approximately 2m individual pixels. This is about twice the amount displayed in a 720p image.
Speaking to Joystiq, Sony’s 3D development boss Simon Benson stated that while the PS3 is technically capable of displaying 3D in the full 1080p resolution – something it will do when 3D Blu-ray movie support arrives later in the year – doing so comes at the expense of framerate.
Movies run at 24fps whereas games run between 30-60fps. Though studios are free to aim for 1080p 3D if they wish, it’s not currently something Sony recommends.

http://www.develop-online.net/news/3...not-seek-1080p