Basically the National Comics imprint is DC's new line, intended to explore "dormant" characters in the DCnU such as Kid Eternity, Madame X (presumably Xanadu) and Rose and Thorn.
"The first issue, written by Jeff Lemire with art by Cully Hamner will center around Eternity. This is the story of police coroner Christopher Freeman. After being given a second chance on life, he finds himself with the ability to resurrect the dead. Freeman uses his new ability to help those he resurrects to find their murderers and to gain closure, so they can continue to the other side."
This could be interesting. :) Plus the cover is neat.