Sega's HD remake of NiGHTS: Into Dreams is indeed coming to Japan. Following an announcement made by its international offices earlier today, Sega Japan made an announcement for the Japanese market.
The announcement was accompanied by this artwork of Nights' head:
In Japan, the game will also be released for both PS3 and Xbox 360 as a download. A release is planned for some time this year (the international release date was listed as Fall 2012).
View the game's Japanese trailer and some screenshots below.
Additional Images (Total 11 Images, Use click action to expand)