My friend and I picked this game up today, and I can say it's very awesome. It immediately grabbed my interest, and I've never touched any of the Megami Tensei titles before. I just have a thing for the types of games where your decisions determine a certain outcome of whatever, and the game's atmosphere really appeals to me as well, with the surrealism of Tartarus and the tarot and religious references, etc. Might have to look into this series a bit more.

The art book and soundtrack that came with the game was pretty awesome as well.

I hope (SPOILER)Mitsuru joins the party sometime.