More info, from the Madman's Cafe (
http://www.mmcafe.com)
"(Namae No Nai Heya) Treasure Co. has made an official announcement through Softbank Publishing's "Dreamcast Magazine" of their decision to release a DreamCast port of their arcade shooting game, Ikaruga.
Originally created for the Sega Naomi arcade system, Ikaruga is currently 99% complete for port to the Dreamcast. Commented by Treasure president Masahito Maekawa, a "Prototype game" is included as a bonus in the DC port, playable by beating the game without any continues.
Ikaruga for the Sega Dreamcast is scheduled for release in September 5th, priced 6800 Yen."