As boredgremlin said, I think the aim of the exercise is to pick up old edition players, especially 3.x and Pathfinder. I also suspect their capacity to recapture large chunks of the legacy crowd will be unsuccessful.
That said, as a happy 4e player, I still think there are lessons that can be learned from why PF players are so happy with their game. Flavor in terms of character customization and skills/spells/archetypes etc make people feel invested. The mechanics and roles for 4e are too out in the open for a lot of players - drawing back the curtain with more flavorful descriptions and seeming less mmo like would make the game more engaging.
I am looking forward to 5e (but desperately hoping for online tools at release).