Concierge.com's insider take:

The fame of the 152-room privately run Sacher has little to do with brocade drapes and attentive service: It's all about chocolate cake. The Café Sacher Wien—where the world-famous (and somewhat dry) delicacy with its apricot middle and shiny near-black top was invented—is still going strong, and still jealously guarding its recipe. But there's also an enchanting hotel attached. Standing opposite the Staatsoper, it couldn't be more central, and it has all the silk wallpaper, 19th-century oils, and Biedermeier furniture you could wish for. A renovation and expansion was finished in 2005; nine of the new suites have huge terraces with stunning views that on clear days extend to the Vienna Woods. There's a new spa as well, run by La Prairie, with (naturally) hot chocolate treatments. Along with the Confiserie and Café, there's the Anna Sacher Restaurant, a classic post-opera stop with its charming winter garden facing the opera house, and the sexy Rote Bar.