Wow, I Love these Designs, These are the people sony should be Recruiting. I like this idea, it has alot of potential, sadly if sony really looked at this, it would be a good idea to think about it. recreating the XMB, I heard Sony was Considering Recreating the XMB later on. You got my Support in this Bro. Keep on making these Wacky designs. Haha!
Nice mock-ups . One thing though, you should use 1280x720 or 1920x1080 resolutions for your images. To more accurately represent a person's TV screen. It dosen't matter that much though since they are just mock-ups.