February 7th is the release of the WiiU edition. I don't know why, but it seems like it's been delayed for all systems that way. I suggest you research a bit about it. And if you have any additional information, please also let me know, as I'm a huge Fist of the North Star fan. I feel you, my man.
I'm not sure I understand completely. But Gamefly will not wait until the other game is released to send the first one to you. It's only for that game. So if you have, say, Tekken in the first slot, and an unreleased game, you will still get Tekken, if available. However, you will not get the unreleased game until said game is out.
To answer the second question, if you send, again let's say Tekken, back and your second game is unreleased, it will go to the next available game. So you will always have a steady supply of games sent to you, unless you clog up your Q with unreleased or unavailable games.
Is there anything else you wish for any members to help with?