This movie is from Trammell Hudson, the guy who created Magic Lantern. He doesn't mention that Magic Lantern had anything to do with the low light performance, so I assume the performance is plain 5DII - however, features from Magic Lantern can help you get the focus, exposure etc much better than stock firmware. (I am sure, however, he used ML when taking this video)
This movie is from Trammell Hudson, the guy who created Magic Lantern. He doesn't mention that Magic Lantern had anything to do with the low light performance, so I assume the performance is plain 5DII - however, features from Magic Lantern can help you get the focus, exposure etc much better than stock firmware. (I am sure, however, he used ML when taking this video)