I agree with formulanerd's assessment.
if input latency is important to you, then HDMI is the worst of the options because TV manufacturers want to deliver you the best picture which means the most processing which means the most latency.
for most games, it doesn't matter. but for timing games like Lips or Rocksmith or anything that depends on minimal lag, HDMI is the worst.
I set up my 360 for my PC monitor via VGA or HDMI-to-DVI when I need minimal lag when in Lips. There's virtually no processing with a PC monitor.
For the TV, even with game mode on, there's still some processing. In order to completely turn off processing, you have to be able to access the hidden maintenance menu for your TV which is meant for technicians only. and even then, there's some TVs that can't be fully turned off.
For the HDTV, I use component when I play Lips. It made a big difference in scoring when compared to HDMI.
For all regular gaming, I use HDMI.
But the bottom line when comparing HDMI, VGA, component, etc. is that it really depends on your TV and how your TV manufacturer handles that TV's input. You can't make blanket statements like "VGA is inferior".