According to Japanese blog My Game News Flash, a new page has shown up on Amazon.jp with a listing for a brand new entry in the Shin Megami Tensei series exclusively for the Playstation 3. This doesn't appear to be Persona 5 either, since those games don't have the Shin Megami Tensei branding coming before it like it does in the West.
Not much else is known, but due to the fact that a page does now exist, and with the history of video game-related leaks that the site is known for, we may have come upon some evidence that suggest the game is close to being completed. We may very well see a high-def SMT game in 2010. How frickin' awesome would that be? Stay tuned to RPGSite for more related news.