There is definitely a ruffle.
I am, by no means, a master couturier, however, I do sew. A LOT. And by "a lot" I mean a lot of formals for young ladies. I've lost track of the number of formals that I've made in the past 15 years but it's easily a couple hundred. Just in the last three months, I've made 6 formals, some far more elaborate than others.
A ruffle doesn't have to have to be gathered at the seam, though that's often how ruffles are created. However, you can also add a ruffle by cutting the fabric for the ruffle on the bias and adding a slight grade outwards, which will give just a gentle, flowing ruffly effect. This is most certainly the case with Madeleine's dress.
I like the sketch a lot more than the actual dress. The waist is, as others have noted, just a bit too high. I'd have dropped the waist maybe an inch or so. And, I probably would have added just a couple inches more of fabric in the skirt at the waist, to give just a bit more poof. I'm not sure
how much more though because it might have looked too frumpy and unflattering on her hips if there was too much extra fabric added into the skirt. But, I definitely would have had more than was there because there's not enough and the gather of the skirt to the waist is just too tiny. It fooled a couple of others, upthread, into thinking that it was a straight seam when it's not. I also think the skirt would have benefited from a more pronounced use of lace, similar to the way it was used on her illusion neckline. Yes, you can see the lace but the sketch just has some oomph to it that the reality is lacking.
Finally, others have noted that there is something not quite right with the cut and this isn't quite correct. There is something not quite right with the fit, especially on the side back section of the dress. I saw a couple of pictures where the fit was obviously loose and while you don't want a dress you plan on wearing for hours upon hours while eating, dancing and celebrating to be skintight, the fit should have been smooth when she was standing.
These are all, in all honestly, rather nitpicky items though. I think the dress is really beautiful. I loved her makeup, the veil and tiara. I really loved the bodice front. It was quite a lovely look and well worth getting up at 7am on a Saturday morning to witness. Especially seeing how affectionate and obviously in love Christopher is with his bride.
