Compared to the EX1, sensitivity is definitely a lot lower, and it's lower than the HF S200 too BUT the EX1 is brighter with the same aperture and gain setting (see the street at night portion of the video [1:53].) Also, the HF S200 will go down to f/1.8, which may be the reason it appears to perform better (see the vase and chair clip at the end of the sequence [2:35]).
In looking at the video, I can't help thinking that the f/3.5 minimum lens might be the biggest mistake...the aperture is just not wide enough. A lot of what attracts people to the HDSLR images they see in demo videos is the incredibly shallow depth of field you can get with a big aperture. But in the examples here you can see that f/3.5 certainly gives you a little blur; but not the big dramatic differences. Of course, you could always buy another lens for the camera...
Don't forget, the EX1 has smaller chips; that's why the depth of field is different between the two cameras at the same aperture (i.e. the f/5.6 clips of the second shot of the fence [0:20].)
Read what Paul has to say here: NEX VG10 and some other cameras/camcorders