OP: 「美しければそれでいい」(Utsukushii kereba sore de ii) by石川知亜紀 (Ishikawa Chiaki)
ED: 「祈りの詩」(Inori no Uta) by savage genius
Both the OP and ED are quite good. The OP is done by Ishikawa Chiaki, who is the lead vocalist for See-Saw.
This first episode of Simoun packs a ton of production quality. Music is great (Sahashi Toshihiko also did the music for Gundam SEED and FMP!). Animation is a combination of CG, traditional animation, and concept art/water-color backgrounds (the latter really reminds me of The Melody of Oblivion, which is another show art director Kobayashi Shichiro has worked on).
This show’s pretty yuri-tastic too…