Photo can't do the color justice. GM dealers (mine has it now) should have a color chart with a sample of the color on it. It carries a different name on the chart, but there is a note at the bottom saying the SSR name for it is Aqua Blur. The color will also be available on the Avalanche and Tahoe/Suburban. The only way you can really see the color change is to take the chart outside, and move it around in the sun.
I'm looking forward to seeing it in real life on an Avalanche before I decide if I like it. It looks like a dark purple on the chart, and probably in real life on cloudy days. The blue/green tone comes to life in the sun. It may look really good, with the color change accenting the curves on the SSR. I'm generally not a fan of green tones - would have liked it better if it played with purple, gold, red tones.
Still waiting to hear if GM will give us a Candy red or tangerine for 06 - what could be more retro?