OMG OMG OMG
It has ended! To cut the story short, this manga's about trying to figure out the meaning of life. The reason why you were born. The concept is pretty hard to sink in and less phenomenal than his previous works. But it speaks my mind very accurately (and in a much better way.)
I love it. But if you haven't read Urasawa Naoki's work before, don't read this one. Try Monster or 20th Century Boys. Especially the latter.