I wonder how that leading edge is to be deiced. And, I suppose, like the first few cabin windows of the 747, every one of those cabin windows would have to be able to withstand a bird strike. Both surmountable, I suppose....
But, if there's fire outside on one side during the emergency evacuation, getting everyone out on the other side in 90 seconds could be a challenge, it looks like a long walk from the back of one side to the exit on the other side!