The real reason is obvious! 800,000 coins stolen by MtGox are being slowly and carefully dumped on the open market, driving down the price.
The flooding of the market by the Goxxed coins will probably continue to keep the price low until they are all absorbed by investors and consumers .. how long will that take? No one knows.
Gox did not lose 800,000 BTC. If they did surely you can show us where and when those coins were taken, yes?
There has been a shift in miners, goals of market speculators, and merchant adoption. I would argue that these are the primary reasons for the continued bear market.