For years now, as Shanghai prepared for the largest world fair ever, those of us who live here have had to put up with buildings wrapped in bamboo renovation scaffolding. We have sighed at paint-spattered sidewalks&mdashwhen there was a sidewalk at all. Often, the pavement itself was ripped off for replacement. Massive chunks of the city were boarded off to accommodate the pile-drivers, and clouds of construction dust choked us as subway lines were added. The historic waterfront Bund was closed off and inaccessible as jackhammers flew over a new promenade.