The new engine has quite a few modifications, including running both direct and indirect injection. The indirect injection will help to prevent all the stuff in the jar in the above picture from settling in the ports and on the backs of the valves. Principally its there for emissions reasons, NOx and PM are lower (especially in certain situations) using indirect injection.
I haven't pulled the two engines apart to compare, but looking at the data, the new car makes more power in the higher RPM at the same boost level. It would appear that as part of the changes Kia have made the engine breathe a little better at higher RPM. Introducing indirect injection will probably have reduced swirl requirements, meaning they can (potentially) have straighter ports, bigger valves and/or a slightly hotter cam profile. Its not going to be major changes, but there's definitely an appreciable difference.