Thanks Andrew, great explanation and it seems 1.3 does offer a lot over the 1.1, 1.2.
The reason I ask is I spent 7 hours on a flight back from Thailand last week with someone in the industry talking about 1.3 like it was as important as air or water and I'm about to embark on a new TV (swaying towards waiting for Pioneer Aussie to get with the program and bring the LX509) and PVR - likely in the form of the Panasonic DMR-BW500 - which we are lucky enough to be getting first.
So I just wanted to know what to look for and check before I bought myself something already a bit out of date - like my Denon AVR4306. Ah well, its a fine excuse to upgrade to the big end of town pre-power combo at some stage.