This has been a huge week for museum news, what with the Guggenheim selecting the winning design for its proposed Helsinki branch, and the Louvre Abu Dhabi, which had been scheduled to open in December, announcing that it would be postponing its inauguration by another year. It has also been a huge year for museum construction, with many institutions—public and private, established and upstart—spending, in total, hundreds of millions of dollars on new buildings, with even more on the way...