An artical from Famitsu.com has released details about the Nintendo DSi bundle along with the release date for KH Days in Japan. The release is scheduled for May 30th 2009, with the price being set at 5,980 yen.

In addition the design of the limited edition Kingdom Hearts 358/2 Days , Nintendo DSi bundle has been shown, with the price with tax set at 24,880 yen for the bundle. Here is a pic below, with the main color of it being black with the top showing various icons in a checkered pattern from the game.

Also here are some other scans, from KH 358/2 days.