Well if you stop and think about it, at least in my mind the aftermarket has gave sonata owners the choice to buy LED lights and if the numbers are high for the sale of the LED lights , then why would Hyundai not want to embrace the LED light trend? Also if you stop and think, the 07 Honda accord sedan and coupe have LED lights from what I've seen on the Honda accords driving around in my state and doesn't hyundai want to more or less beat these cars in sales, so if LED lights are the "hot in thing" then I believe hyundai would want LED lights..
I think the sonata looks great with LED lights and that is one of my future upgrades to my sonata, If I walked into a Hyundai dealer and had the chance to buy a sonata with LED lights then I would. I think most people my age would want LED lights, Anything that is flashy yet affordable is kool to me as long as it doesn't look cheap and the LED lights look good with a modest price...