Translated from Japanese:-
http://www.microsofttranslator.com/BV.aspx?ref=BVNav&from=&to=en&a=http%3A%2F%2Fd.hatena.ne.jp%2Fyoda-dip-jp%2Fsearchdiary%3Fword%3D%252a%255bGame%2520Compare%255d
* PS3 set to full range of HDMI, as for 360 image quality of HDMI is set to the maximum.
* The 360 version 5.8 gigabytes (GB) of any installation, PS3 version 1.9 gigabytes (GB) of what needs to be installed.
^ That's all I can get from that site.