Difference between 60hz and 120hz?

[platformmaster918]

Lafiel said:

PCs can easily output in 120Hz, so 120Hz in a monitor is useful, but consoles don't output in more than 60Hz, so 120Hz in a TV is a gimmick, as the additional 60Hz are made up frames by the TV. That introduces additional lag, as the TV has to process those extra frames by comparing 2 actual frames and calculating an intermediate step.

That method alone introduces a 1 frame (1s/60 = 16.67 ms) of additional lag, but ofcourse the processing itself takes up time aswell and so on. It's just not useful for console gaming.

I see and as for next gen gaming?  Also does it effect movie viewing?