WoW, it's been a long time since I have seen an anime this good. Vivisqueen summed it up very well in her review so refer to there for more, but let me just say I don't give out many 10/10's but this one earned every point. From the haunting music, to the cast of unusually interesting characters, some I liked others I loathed but all of whom held my attention during each and every episode. Many times this anime kept me guessing about what would happen, a truly enjoyable factor for me.
Though technically classified as a "Mecha" show, don't go thinking this about some robots going at it with fast action and awesome special effects. This is an anime with a deep and involved storyline that will drag you in and keep you in the same place with each pilot of Zearth. The robots are a footnote to the pilots and there is nothing "Gundamish" about them.
I don't dare say anymore less I ruin some of the plot but definitely add this to your want to watch list!