Oh yeah, sorry I forgot about that. Shikigami no Shiro Evolution is a Japanese only Xbox exclusive remake of the first game, which also got ported to the Xbox prior to Evolution's release. Evolution features new and improved enemy AI, a few new playable characters, and the new Evo.Mode game mode that remixes some of the stages. If you've got a TV that can support true shmup aspect ratio, it also includes a vertical mode.
Other than that, it comes in a very attractive package where the kanji, 式神の城 shows up in really cool shiny letters (the kind a scanner would ruin if one tried to make a scan of). It also has a mini artbook the size of the manual which is really cool.
Still, Evolution is just a enhanced version of the original. The sequel is longer and more fun to play.