If they stream the video and you play it through another server then yes. Maybe it will be all games will download in an efficient way so that after the core games files are downloaded it lets you access currently downloaded sections of the game.
Not exactly the same but there abouts. What it does is load in enough data to begin your game. It will probably work out how long it will take to download the entire thing and then apply that to how much you'd have to download before you could start playing. For instance, If a game is 4 hours long and it will take an hour to download, it would be easy for Sony to come up with a system that allows you to start playing the game when only a quarter of the data is in. However, this system isn't going to work for every game. It wouldn't work for a game that you could access all areas from the very beginning. The streaming service on Gaikai doesn't download any data, it simply uses your PS4 as a receiver.
I can see where your coming from, and I wouldn't doubt an open game like Fallout or Elder Scrolls couldn't run without a lot of the data pre-installed; however a game like Uncharted where it's more linear could work in theory with downloading in sections.
OT
I do like the idea every ps4 game can be demo'd in a sense before purchasing, which that alone further confirmed which side I'm joining when it's released. I HATE the idea of risking purchasing a game I don't like; and PS+ did help a lot with making about 85% of what I "thought about" free so it's no $ out of my pocket just to try and return to the store later. My only question is although we can demo it, unless I missed it somewhere I didn't find how long we could play the game(s). I know current PS+ it's 1 hour however I don't know if that will carry over to the 4 or not.
It might be like the system Blizzard uses on PC. You download the first couple gbs and the game is playable while the rest downloads. I don't know exactly how this system works though.
I'll stick with physical media, I like the idea of either selling or giving the game away after I'm done with it. with digital downloads on a console it is ALL WIN for the Developr and ALL LOSE for the consumer.
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I can see where your coming from, and I wouldn't doubt an open game like Fallout or Elder Scrolls couldn't run without a lot of the data pre-installed; however a game like Uncharted where it's more linear could work in theory with downloading in sections.
OT
I do like the idea every ps4 game can be demo'd in a sense before purchasing, which that alone further confirmed which side I'm joining when it's released. I HATE the idea of risking purchasing a game I don't like; and PS+ did help a lot with making about 85% of what I "thought about" free so it's no $ out of my pocket just to try and return to the store later. My only question is although we can demo it, unless I missed it somewhere I didn't find how long we could play the game(s). I know current PS+ it's 1 hour however I don't know if that will carry over to the 4 or not.