The lack of mascots was just a symptom of one of it's weaknesses, the lack of games that is Sony and Sony alone. PSX had a a lot of default mascots, but they failed to capitalize and assumed they will always be good and remain exclusive to Sony. When they did start to develop their own mascots, it was far too late. They now lack the expertise, talent, market presence or vision. Sack Boy is the end result. Home isn't helping them. It's something they can't sell, nor is it something that hasn't been done before, but better. The lack of continuity opens them up every generation to new competition.
That's just the videogames division. They haven't made any cuts in movies or the PS lines. Yet.
Blue Ray has done nothing but tied them to a war they shouldn't have fought. They only needed torpedo HD-DVD so they can some out with truly superior product in the future. Now it's stuck is a war with DVD that it can't win. The HD market is confused as there is no set standard. HDMI continues to cause more problems than it solves, for marginal gains to protect something people aren't buying. Itunes and the Ipod kills them on the music stage.
Sony not being able to work around the strengthening Yen is shortsightedness at it's best. Sony is looking like the Big 3 car makers in the US.