Let's say x720 has 4gb for games, I think devs will use PS4 as the primary console and porting games to X720, dumbing them down if needed. Whether or not games comes to Wii U as well is a matter of how big the instal base is and how much it'll cost to dumb down a game sufficiently for it to run on 1GB...
I'm on Twitter @DanneSandin!
Furthermore, I think VGChartz should add a "Like"-button.