While Microsoft isn't set to release Office 15 as a public beta for a few months yet, the company provided a sneak peek to a select group of businesses, partners and OEMs on January 31st in the form of a technical preview. Despite the testers being required to sign non-disclosure agreements, some screenshots and details have started to leak out from those who received access to the beta.

The most immediately obvious change is the influence of Microsoft's Metro UI, which was originally created for Windows Phone 7 and will be seen in Windows 8. In Office 15, Microsoft looks to have merged the Metro UI with its much-maligned Ribbon interface that debuted in Office 2007. The ribbon's default setting appears to be collapsed which, along with a fullscreen "backstage" menu, results in a much cleaner look - although users will be more concerned with how easy it is to use.

Like Windows 8, Office 15 also looks set to embrace touch to enable easier use on tablets and touch-enabled PCs. Windows President Steven Sinofsky has said in a blog post that desktop versions of Word, Excel, PowerPoint and OneNote optimized for touch and minimal power usage will be included with Windows 8 on ARM (WOA). A (currently non functional) Touch Mode button suggests that users will be able to switch between touch and mouse/keyboard inputs depending on the device on which they are using the application.

Microsoft is yet to respond to the leaks - and probably won't - so we'll just have to wait and see if they - and others, such as possible Skype integration - prove correct or not. The company has said is that the Office 15 public beta will be available this northern summer, with expectations that Office 15 - or whatever the new version of Office will be called - will be released before the end of the year. Additional leaked images can be seen at The Verge.

Sources: The Verge, ZDNet, MSDN Blog, Office Blog