MAJOR UPDATE
The announcement trailer for M-17 has finally been posted on YouTube!
http://www.youtube.com/watch?v=_7xCKUdOl1I
It seems that the sources have been accurate. The short clip shows a dark, foggy sea and just as the camera zooms in through the "Production of Movie 17 Confirmed!" text, a ship materializes out of nowhere (that's where the "rises out of a dark sea" must have come from). Also, the "illumination" mentioned is what appears to be a full moon over-glared. There also appears to be an island in the distance, which none of the sources mentioned. It doesn't appear to be a submarine (as some people suggested...) and it also doesn't look at all like the St. Aphrodite from M-9. After a close comparison, they're different shapes.
The way the ship appears out of nowhere is interesting and the music gives it a very "ghost ship" feel. If the producers decide to take that route, I'm going to be really excited. Now, we wait for the promotional poster...
[Video link has been added to first post for easy access]