"Unlike the original DS, the backlight on DS Lite cannot be turned completely off. "
Sounds like the screens are completely backlit now instead of still being reflective and backlit like the original DS model. The unfortunate thing here is that it sounds like the screens will completely die outside, whereas on the original model under good lighting it was still visible and in some cases looked better than it did with backlighting. I wonder, since you can't turn off the backlight on the SP mkII, does that die outside too? And I wonder what'll happen in Viewtiful Joe? That game has an option to turn off the backlighting as well as Ashpalt Urban GT and I wonder if that'll screw with them in any way.