Microsoft updated its Office Next blog with details about Office RT, the upcoming Office release for the ARM-based Windows RT platform. The post confirms many of the rumors we've heard a couple of weeks ago, the software giant reveals preview versions Word, Excel, PowerPoint and OneNote will ship preinstalled on Windows RT devices. Once the final edition of Office Home & Student 2013 arrives, Windows RT devices will be automatically updated with the final edition for free via Windows Update. Consumers can expect the update to arrive in early November through January depending on their language.

Microsoft says Office 2013 RT automatically enables touch mode, and claims they've optimized the applications to maximize battery life and to use less resources. There are other key differences between Office 2013 and Office 2013 RT though, the latter one lacks Outlook and Microsoft now confirms rumors that the two office suites will not be 100% compatible. Here's a list of features that are missing from Office 2013 RT:

• Macros, add-ins, and features that rely on ActiveX controls or 3rd party code such as the PowerPoint Slide Library ActiveX control and Flash Video Playback
• Certain legacy features such as playing older media formats in PowerPoint (upgrade to modern formats and they will play) and editing equations written in Equation Editor 3.0, which was used in older versions of Office (viewing works fine)
• Certain email sending features, since Windows RT does not support Outlook or other desktop mail applications (opening a mail app, such as the mail app that comes with Windows RT devices, and inserting your Office content works fine)
• Creating a Data Model in Excel 2013 RT (PivotTables, QueryTables, Pivot Charts work fine)
• Recording narrations in PowerPoint 2013 RT
• Searching embedded audio/video files, recording audio/video notes, and importing from an attached scanner with OneNote 2013 RT (inserting audio/video notes or scanned images from another program works fine) 

Microsoft Office RT will lack features and be late