This is that 'Millenium Falcon' object they found! There are some sonar images available of it now and they're working on making these 3D. Although sonar and satellite images of the ocean floor are know for being somewhat unreliable, (the object only rises about 3 or 4 metres from the ocean bed, making detailed sonar images suspect at best, but human visuals seem to back the pictures in this instance) there definetly seems to be something pretty interesting down there.
Other reports say that the rocks down there appear scorched and that the object gives off a higher level of radiation to its surroundings (luckily, not dangerous levels.)
I'm very skeptical at the whole "EMP shield" thing; no one of any expertise or authority has said anything about an EMP and from the descriptions of what happened I'd say that anyone claiming that any form of EMP is involved probably doesn't understand what an EMP actually is. I read that a satellite was unable to look directly at the object, but if the object was giving off an EMP that reached into space we'd know about it. At the very least, nothing on the boat would work, let alone an underwater camera.
Speaking of which, let's not forget that electronic equiptment doesn't like being under water or in low temperatures - least of all because it forces batteries to 'work harder'. They reported water temperatures of -1 degrees. And yes, contrary to what some keyboard conspiracists think, this is possible.

I'm thinking there might be some sort of crashed asteroid down there, which could explain the burnt rocks and radiation at least. There's no real volcanic activity in the Baltic so that's not it.
I look forward to seeing where this goes, whether there's something down there or not!