Greg's Cool [Insert Clever Name] of the Day: Microsoft Format and Specification Documentation Refresh ("Significantly changed technical content") [Updated: Includes updates for Office 15 Technical Preview ]

Microsoft Office File Formats Documentation

The Microsoft Office file formats documentation provides technical specifications for Microsoft proprietary file formats that are implemented and used in the Microsoft Office system.

Microsoft Office Protocol Documentation

The Office protocol documentation provides technical specifications for Microsoft proprietary protocols that are implemented and used in the Microsoft Office system.

Microsoft Exchange Server Protocol Documentation

The Microsoft Exchange protocol documentation provides detailed technical specifications for the Microsoft protocols that are implemented and used by Microsoft Exchange to interoperate or communicate with other products. It also provides technical specifications for extensions to industry-standard and other published protocols that are used by Microsoft Exchange.

Microsoft Exchange and Microsoft Outlook Standards Documentation

The Microsoft Exchange and Microsoft Outlook standards documentation describes how Exchange and Outlook support industry messaging standards and Requests for Comments (RFCs) documents about iCalendar, Internet Message Access Protocol – Version 4 (IMAP4), and Post Office Protocol – Version 3 (POP3).

Microsoft SharePoint Products and Technologies Protocol Documentation

The Microsoft SharePoint Products and Technologies protocol documentation provides technical specifications for Microsoft proprietary protocols that are implemented and used in SharePoint Products and Technologies.

Word, Excel, and PowerPoint Standards Support

This documentation provides detailed support information for the Open Document Format (ODF) and Open XML (ECMA-376 and ISO/IEC-29500) file formats implemented in Microsoft Word, Microsoft Excel, and Microsoft PowerPoint.

I haven't seen a broad change history document [Update: I have now, see below], so had to randomly review a few doc's to see what changed. In those I checked, looks like the doc's have had a "major" update.

These are those kinds of doc's that if you need them, you know you need them and a refresh will be news to you. If you don't, you won't care less. That said, if you're ever in need of the specifications/format documentation for Microsoft's major tech items (like Office, SQL Server, SharePoint, Exchange, etc) then these doc's should be one of your first stops. But don't expect light reading...

UPDATE 1/30/2012 @ 5:28PM PST: Looks like the team heard my cries of "What's new!?" and have detailed it for us here...

Office Interoperability - Office 15 Technical Preview - Open Specification Update

The January 2012 release contains updates made to Microsoft Office Protocols documents since the June 2011 refresh. It includes updates and new documents related to the Office 15 Technical Preview.

Microsoft Office File Formats links:

Full documentation set (zip): Microsoft Office File Formats Documentation

Summary of changes (pdf): [MS-FFCHGTR]

Microsoft Office Protocols links:

Full documentation set (zip): Microsoft Office Protocols Documentation

Summary of changes (pdf): [MS-OCHGTR]

SharePoint Products and Technologies Protocols links:

Full documentation set (zip): SharePoint Products and Technologies Protocols Documentation

Summary of changes (pdf): [MS-SPCHGTR]

Word, Excel and PowerPoint Standards Support links:

Full documentation set (zip): Word, Excel and PowerPoint Standards Support Documentation

Summary of changes (pdf): [MS-OSTANCHGTR]

The following new specifications have been added to the Office Protocols documents:

...