Ikaruga is coming this week, April 9, according to the game's website. There's no official word yet from Microsoft, but we wouldn't find the date surprising, as it was leaked once before on the Japanese Xbox site. The game was also "outed" for an April release by the UK Official Xbox Magazine and has reportedly been on PartnerNet since January. Our fingers are crossed that this release date will stick, and come Wednesday, we can enjoy some mind-blowing, color-coordinated space shooting.
Update: Confirmed by Microsoft's Gamerscore Blog for this week.