i veto the Dolce. while it's pretty, i wouldn't say its got anything to do with Haute Couture. unless all the crystals are elaborately handapplied in some atelier in Paris...
high prices =/= demi-couture.
it has to have something beside embroidery to really "elevate it" from just expensive and elaborate RTW. a certain artful touch. some special technique.
like those t-shirts from The Row with the single seam in the back which was sewn in a certain special couture technique (forgot the specifics).
I'm not seeing why we need to argue about what is and isn't demi-couture, as there is no formal definition and it doesn't have any of the firm rules of haute couture, but price seems to be just as good of a way to separate it from normal RTW as anything. Even some of (in my opinion) the best couture has little in the way of special techniques. Look at Chanel couture, for example. Beautiful clothes, but most of them (sans the S/S09 collection) owe their brillance to beautiful beading and embellishment, not to sewing skills. (By the way, the Row's back seam is just a French seam, if I remember correctly, and it's not something that is all that special.)