One of the clever parts of Sony's PSN winback program is that it brings people into the PSN store. I've been there a few times to pick up Rock Band songs or activate DLC that came with games, but it never occurred to me that you could download games that ship on Blu-Ray. Turns out that they're actually smaller than your average MMO client. On top of that, some deals are actually competitive with discs - for example, Assassin's Creed 2 is available on the PSN store for the same price I'm seeing for discs online, but the PSN version comes bundled with all the DLC. I don't know that I'd pay extra for the DLC if I already had the disc, but the digital version is a no-brainer if it comes with extra levels for free.
Digital downloads have been bumping up against retail for a while now in the MMO-scene. I actually picked up Rift's digital download, and probably would have picked up the day 1 Cataclysm download if the local brick and mortar store hadn't offered a promo that beat Blizzard's price. Last week we heard that EA is cutting out the digital middle-man for SWTOR, by reserving the game's download version for their own new download service. I'm not sure what to make of this move, but I'll concede that I'm not sure what Direct Download contributed to my Rift download other than undercutting Trion's own price by 20%.
I don't think we're going to see console games disappearing from stores the way that PC games have for years now anytime soon, but it certainly looks like the technology and the bandwidth are starting to catch up with the financial incentives - fewer middlemen and the ability to completely cut off resales - for this to happen.