I have run more power from Asus boards as well, even from my laptop. To be honest, EVERY Asus board I had could power a 2000ma laptop drive. My old P35 DS3R would NOT. But my X58A UD5 sure does. My Samsung screen's usb ports seem to run anything.
I own a GA-X58A-UD3R, and it's a great board. Like builderbobftw said, I now understand the full implication of the 3x USB power sticker.
I do notice that I'm able to power some laptop drives on my gigabyte that other computers won't too. So, I don't need another cable to connect my drive to the PC. It's just another incentive to buy a Gigabyte board. Of course you can spend $3 and get a Y cable, but this makes it simple. It's a useful little feature.
I find it really stupid that the manufacturers gave USB only 500mA. Why not give it at least 2 or little more amps? Have to use that Y cable every time, and on some computers/laptops even that is not enough...