A preview version of
Microsoft Office, Office Home & Student 2013 RT, designed for tablets running the RT operating system, will ship in the fall or early winter, according to this ComputerWorld article. The operating system will be pre-loaded on tablets and not sold as a standalone product.
Microsoft says it will be slimmer and trimmer than its desktop predecessors. Power-saving capabilities will be enhanced to save battery life on mobile devices, and certain functions will be cut out to save disk space on the typically smaller SSD drives in tablets.
Some of the functions that will be cut out in the new release, according to the article are:
"macros, add-ins, and features that rely on ActiveX controls or third-party code, as well as legacy features such as the ability to play older media formats in PowerPoint and edit equations written in Equation Editor 3.0, used in older versions of Office."
Some of the clip art content will also be cut out and made available online instead.