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Doesn't mean it does anything with the 96%

Charcoal absorbs about 98% of incident light, and it doesn't even use plastics

Indeed, it's an advantage over cells that reflect more light, but it isn't in itself enough to have an efficient cell.

They haven't released the actual conversion efficiency numbers yet, but from the qualitative talk about it, it sounds very promising. That's one tech that I'll keep track of.

Also handy to know: does it last very long?
Like long enough to feel like your better than your neighbors for being part of the "solution" or long enough to actually be good for the environment? The Former Yes the latter? Well if you even feel the need to ask the latter you are Global Warming Denialists, so I cant talk to you.
I can finally get rid of all my white solar cells.
Yawn...what would really be intersting is if someone wrote an article surveying the best commercially available solar technology over the last 10 years with comparable price points and performance. Then we might get some understanding of how much progress is really being made and where we might be headed.
Original source (via discrete link at the bottom): http://media.caltech.edu/press_releases/13325

Choice quotes from original:

The silicon wire arrays created by Atwater and his colleagues are able to convert between 90 and 100 percent of the photons they absorb into electrons

The next steps, Atwater says, are to increase the operating voltage and the overall size of the solar cell. "The structures we've made are square centimeters in size," he explains. "We're now scaling up to make cells that will be hundreds of square centimeters—the size of a normal cell."

Very misleading title. From the article: "arrays absorb 96 percent of incident sunlight at a single wavelength." Sunlight is hardly monochromatic, and is in fact spread out over a very broad spectrum. More specifically, these cells can ostensibly absorb 96% of light with wavelength <= 1130 nanometers, which corresponds to the band gap energy of silicon.

Also, the article does not address the important fact that absorbing light is not tantamount to converting it to electrical energy. Namely, any energy that a photon carries in excess of a semiconductor material's band gap (silicon's is 1.1 eV) is wasted as thermal energy. For silicon, which lies near the tail end of the sun's spectral curve, this means that about 61% of absorbed sunlight goes to thermal losses.

well then, its obvious they are thermal solar collectors for heating water :)
What's nice is that it is flexible! You could create a computer in a jacket powered by solar cells :)
It uses very little expensive material, it can be printed roll-to-roll, and it absorbs a lot of light. Seems like a very good foundation for a solar panel tech, though it isn't there yet.