I would imagine it's just like a regular DRL, just in a different shape. BMW has them, maybe look up their cost and get an idea. My guess is that it will be cheaper than BMWs, because GM was trying to keep the cost of the Camaro down, and if this was too expensive, they wouldn't have done it.
And...I don't know if it's functional like a foglamp or not, but if it's just for looks, then it would be nice if they used LED technology for cost and durability.