I would agree with a lot of the opinions that multiple backgrounds would replace most of the corner and border issues. Let’s face it, corner radius (and handfull of other corner styles) will only get so much mileage. But a good multiple background ‘module’, that makes placement a breeze would be IMO far more beneficial. It provides the designer with more flexibility (multiple borders, custom border styles, custom corners, shadows even).
And the good people developping IE won’t be perplexed with a more complicated box model : )
Ron van den Boogaard: excelent post.