It is sony's fault. When was the last time you bought a walkman? They have not been as technologically innovative as they could have. Tv's are a crap business, small profit margin for all companies but sony has fallen behind here, sony has some great cameras and camrecorders but the average person doesn't buy them anymore when you already have a smartphone that will produce decent results. Honestly the problem with sony as a whole is that they still had this mentality that everything we do will sell, maybe in the 80s this worked but times have changed. As a whole they just need to cut down everywhere and focus on making something that everyone will want. They can do it, they invented the amazing walkman and they still have the resources to come up with their next big innovation.It is not Sony's fault. People are spending less with entertainment, Video Games are not the only affected industry, also they (Sony and Nintendo) developed many things on fiscal year of 2011.
When a company spends a lot with R&D and sell less than was expected, the result is not good. 2012 will be tough too, I think, but 2013 the expenses with R&D probably will decrease (PS4 and WiiU will be released until 2013, right?), and I hope to see VG industry selling a lot.
EDIT: Android and iOS will not kill "regular" gaming yet. I saw many gamers saying that, but I don't see Nintendo or Sony blaming mobile gaming.