Well it wasn't just Sony that had it's credit rating relegated to junk but Panasonic as well.
I suspect that part of it is cost, with competitor's like Samsung better responding to the market, and offering just as good products as Sony. If I were to purchase A sony TV for example over a Samsung I suspect I would pay more for the Sony. So If I can save myself a hundred and get as good why not save the hundred.
I think it's more the TV/DVD production side of Sony that's run into trouble. So rather than any films what about the PS4? After all the PS3 is what the third most popular of the 360/PS3/Wii generation consoles. The PS2 was number one If I recall correctly.
A couple of articles related to this news.
http://www.bbc.co.uk/news/business-20443294
http://www.bbc.co.uk/news/business-20449083