To me, the most important part right now of this whole thing is what you can deduce from that outside shot that's been quoted a few times above. For example, the things that I notice:
1 - and perhaps most obviously, the new sections of roof do not in any way meet up with the old roof. To me this is a very strong hint that they have plans to do over the east and west stands too, possibly in the near future, as the look of the stadium is a little out of kilter with the ends being much higher than the sides.
2 - The glass frontage on the outside of the new ends. I guess they could just leave it as a goldfish-bowl type deal where you can see into the stand clear as day, and when it's first opened it almost certainly will be, but I'd guess that they will cover over the glass with something. I'd like to think that they will try something fancy, i.e. the Allianz' colour changing walls, but I suspect instead it will just have motifs plastered on, in the style of the current "countdown to the title win" banners they put up last year showing shots of the QPR game. This could still be pretty impressive - the glass frontage is not broken up by external struts or by spirals, so imagine having one or two images that are each 50m tall and 100 wide. It could happen, and it would be visible from a way away, as the south end of course looks over the Ashton New Road.
3 - Follow the edge of the glass frontage around and you see it would intersect the spirals. If they do ever expand the stadium so that it matches all the way around, I think we'll be saying goodbye to the spirals.
4 - On the external view you can see a little rectangle of white just outside and on the end of the glass frontage, and there's another less-visible one perpendicular to the first, going inwards towards the stadium. You can see the same thing on the end of the glass frontage on the north side, up above the leftmost spiral, too. I think these must definitely be considered entrance points. I wonder if, therefore, this means an end to the gates spread all around the edge and instead them being replaced by some kind of high-capacity entrance points on the edge of the ends. This would probably tally up with the story of Wembley-style escalators to get to the third tier.