In general I've been trying to keep clear of the Star Wars 7 The Force Awakens rumors, but I was looking at some old shots of the models from the original Star Wars trilogy, when the image of the Millennium Falcon came up and I realized why something I'd seen from a leeked Episode 7 image didn't seem right.
On the left is a shot from the original model, on the right is from the set of Episode 7. You can clearly see multiple differences, not just subtle, but obvious differences. I highlighted just a few in red.
You'll notice several more.
I'm sure everyone on 7 is working hard to get every detail right, but this is going to be a big, difficult thing to get everything right on.