Microsoft added a new 'Tell Me' field to its free World and Excel web apps. 'Tell me' uses "a mapping engine to help users discover functionality based on what they want to accomplish," a Microsoft spokesperson said. In other words, Tell Me isn't currently using Bing as its back-end; it's using proprietary mapping technology. But, the spokesperson said: "The future of Tell me will definitely include Bing.
With the latest update, the four web apps (Word, Excel, PowerPoint and One Note) look flatter. There also seems to be a bit more spacing between buttons, possibly to make Office Web Apps easier to use with touch screens.