http://www.ign.com/articles/2013/08/20/playstation-4-release-date-revealed PlayStation 4 will release on November 29th, 2013 in Europe, Australia and New Zealand and November 15 in the US and Canada. Revealed during Sony's Gamescom 2013 press conference, the $400 next-gen console's date will compete with Microsoft's November release window for Xbox One. PlayStation 4 has already surpassed 1 million pre-orders worldwide. It will launch in 32 countries. You can pre-order the PlayStation 4 now.
Nope. Sony has already stated weeks ago that the PS4 will not be backwards compatible with PS3 disc games.
It will have a streaming thing where you can stream older games like that, but i think you'll need to subscribe to PSN Plus.
I'm already a PlayStation Plus member, from everything I have read they will have a lot of PS3 titles available to download and play on the PS4, but it will not play your PS3 discs. I don't know how PlayStation would know whether you own the disc or not so I'm assuming that if you own a disc game they will not give a free download of the PS3 game.