"In the US, the decoration on the quilt comes almost exclusively from the patchwork blocks used to form the quilt, rather than any decorative stitching."
largely true, as Liz said. But we do have a few folk who do white or solid with the stitching as the design. It's not really rare to see a "hybrid" version, combining patchwork fabric and a separate, but harmonious, design in the stitching.
The one we made is extremely simple by comparison to what several local women do.
                        Dean