It's useful. And easy. And it's quite of fun.
You just upload any photo and it gives you the colours that match or compliment the main colours in that pic.
How handy.. especially for those of us who do not have a keen eye for colour but still want things to look good.
Here's what I got from a few of my favourite piccies from the Hubble Telescope
I actually really like all three of the palettes generated from these images.
The less wedding related the better they seem to turn out.