Probably day one for me as well. I only ever played MGS4 back when it came out and then again two months ago. I know it gets a lot of hate but I enjoyed it and it made me laugh at how ridiculous some of it is.
But this still looks entertaining and like a good play so that's what I'll do! Too bad I'll have a my first newborn three weeks prior - I think I'll be preoccupied! (And not "too bad," I'm looking forward to being a parent)