In a blog post today, Microsoft Corporate VP PJ Hough announced the beginning of a Technical Preview program for Office 15, with what he called “the most ambitious undertaking yet for the Office Division”:

With Office 15, for the first time ever, we will simultaneously update our cloud services, servers, and mobile and PC clients for Office, Office 365, Exchange, SharePoint, Lync, Project, and Visio. Quite simply, Office 15 will help people work, collaborate, and communicate smarter and faster than ever before.

Hough also announced that while the Technical Preview for select customers is under NDA (and we’ll see how long that lasts), an Office 15 public beta will become available “later this summer”.  It’s possibly

Not much is yet known about Office 15.  Mary Jo Foley has heard that there may be a new product in the line.  The new application, apparently code named “Moorea”, may be an offshoot of Office Labs’ “Canvas for OneNote”, described on the Office Labs site (the page is no longer available except in cached form):

Canvas for OneNote allows you to navigate and edit notebooks in a new way by providing a high-level canvas-view of all your content. The prototype lets you zoom and pan around; view and organize content in new ways; add new pages right where you want them; and even locate pages in a timeline view.

However little else is known (yet) about Office 15.  How fully will it embrace “Metro”?  Will the “Ribbon” survive Office Metro-fication?  How fully will SkyDrive be baked in to Office?  And how will the Microsoft IM portfolio adapt to the acquisition of Skype?  Will Lync survive?  Will Messenger?  One good thing, at least we’ll be finding out the answers to these questions and more by “later this summer”, if not well before.