FIX for screen separation issue! UPDATED 8/02
So rather than sending back my Nexus 7, I decided to give something a try. I removed the back casing, which is very easy to do. I used a small flat screwdriver where the "leather" meets the plastic and gently wedged it in. The case popped right open and was easily removed. I then tightened all of the small phillips screws around the outside of the board on the back of the screen.
This immediately cleared up the creakiness and play that i was experiencing on the left side of the screen. I tightened all screws and not just the ones on the left side. Do this at your own risk, obviously, but this immediately rectified my issue!
So on Friday, I noticed a slight creak returned. I removed the black strip of foam that has been discussed in this thread. Since Friday, with heavy use, no creak, no play, no screen rise
I'll update again later in the week to confirm it hasn't returned.
Since removing the sponge, the play in the screen and the creaks have not returned. I see others havent had as much luck with it but, for me, I can say it did the trick.