A leaked Microsoft roadmap shows that the next version of Office won't ship until the first quarter of 2013, according to the Dutch developer who found the document.

Maarten Visser, the CEO of Meetroo and a decade-long Microsoft partner, stumbled upon the roadmap a week ago after clicking on a link posted on Microsoft's Dutch website. The PDF was not password protected.

"I'm always curious about the roadmaps," said Visser in a YouTube video he posted yesterday. "For me, since we build SharePoint applications, the release of SharePoint 15 is an important thing. The better I know when this will happen, the better I will be to ready my products before launch."

Visser's Meetroo is building project management software that relies on SharePoint.

While Visser noted that much of the information in the roadmap was already known -- that Microsoft will release a public beta of Office alongside betas of supporting products like SharePoint and Exchange -- he pointed out that the document pegged the suite's final release as the first quarter of 2013.

The roadmap's date for the public beta, however, doesn't jibe with Microsoft's recent comments.

On the roadmap, the Office beta was marked as smack-dab between the third and fourth quarters. While Microsoft has not yet revealed a detailed timetable for Office, two months ago the executive who runs the Office group, P.J. Hough, said "Everyone will have the opportunity to try the Office 15 public beta later this summer."

To meet Hough's "summer" promise, the beta would have to appear in the stretch between late in the second quarter and near the end of the third.

Microsoft has not assigned the next Office an official name, but has used "Office 15" as a placeholder. The roadmap used the same label.

Another section of the roadmap showed timelines for Windows -- both client and server editions -- as well as Internet Explorer 10 (IE10) and Windows Phone.

Windows 8's schedule was bare, with only last September's Developer Preview marked, and others, including Windows Server 8 -- which is expected to launch at the same time as the client editions -- simply showing a label of "Historical Release Cadence" that stretched from mid-2012 through early 2013.

Most experts anticipate a formal release of Windows 8 -- at least the desktop version -- in the fourth quarter, possibly October, because they assume Microsoft wants new Windows 8 PCs on shelves during this year's holiday sales season.

IE10's launch was marked as some time in the second half of 2012.

One analyst said the roadmap demonstrated just how opaque Microsoft is when it comes to disseminating information to customers. "Not only do ISVs [independent software vendors] and corporations need to know release dates, but as a customer, you need to know them, too," said Michael Cherry of Directions on Microsoft.

"Everyone needs a timeline that's dependable, but it's not enough to just give us dates," Cherry said, referring to the leaked document. "You have to give us descriptions why those dates are what they are."

That's something that Microsoft doesn't do early enough in its development process, Cherry said, making it nearly impossible for software makers like Visser, companies that craft their own applications for internal use, and customers -- especially enterprises -- to make intelligent decisions on developing for a new platform or migrating to it.