It won't be on DVD for quite some time, if at all. The 3D projection system was new and the band invested a lot of money in the 3D system : around $15m if I remember, and I think the technology is the stuff that is at the bleeding edge of most 3D cinema presentations at the moment. As far as U23D's exietence is, it seems that it would be incorrect to release a DVD in 2D as it is, by its very name "U23D". If I were U2, I'd make it a 2D/3D Fanclub DVD. But I'm not.