Something a bit similar to Fallout 3s, from what I've read. Enemies will still scale, but if you visit a cave at level 1, the creatures there will always spawn based on that level 1 player.
But that's what the last system was supposed to do as well, but because of the character leveling system in the game, a person could easily become quite overpowered or quite underpowered as well.
Further, this doesn't address the issues of having NPCs eaten by monsters every time they leave the city once you're past level 10.
So it should hopefully work out well. And yes, a console option for console users would be nice for things like broken quests and getting stuck places, but hopefully Bethesda will catch that all in QC, or release patches for it later. At least (hopefully anyway) there won't be any bugs inherent to the engine as they wrote it pretty much from the ground up, so unless they did a terrible job writing it, I imagine there will be fewer bugs.
We can hope. I would have hoped for that last time though too - in fact I did. It wasn't there.
Thus my concern, and why I wanted to voice that concern.