Atlus’s website has been updated with this banner as well as a series of cards bordering the site’s content. Rumor has it that the announcement will be for a US release of the Yggdra Union PSP port. This seems like a fair guess to me since cards are an integral part of Yggdra’s battle system. Also the ones on Atlus’s site are identical to the back of the cards in Yggdra.
This is still just a rumor, but we will find out the truth tomorrow. Since the Yggrda PSP port has been out in Japan for nearly a year now, we can probably expect to find copies hitting shelves before the year is out. Yggdra Union is part 2 in the 4 part Dept. Heaven series.