The SP1 updates for the Windows Installer (MSI) versions of the Office 2013 desktop products, and for the SharePoint 2013 server products, are available from the Microsoft Download Center today, as well as from Microsoft Update and the Windows Server Update Services (WSUS) catalog.

After a 30-day period, SP1 will begin releasing as an automatic update through Microsoft Update.

Those who have an Office 365 subscription will get the SP1 changes automatically in their next regular update.

SP1 provides fixes to improve general stability, functionality, and security in Office, SharePoint Server, and related products. Among the functionality improvements and changes are the following:

• Compatibility fixes for Windows 8.1 and Internet Explorer 11.
• Better support for modern hardware, such as high DPI devices and the precision touchpad.
• New apps for Office capabilities and APIs for developers.
• Power Map for Excel, a 3D visualization tool for mapping, exploring, and interacting with geographical and temporal data in Excel, is now available to Office 365 ProPlus subscription customers.
• Improvements to the Click-to-Run virtualization technology that installs and updates Office 365 desktop applications.
• SkyDrive Pro is now OneDrive for Business.

A detailed list of SP1 fixes is available for download. Additionally, SP1 includes all the Public Updates (PU) and Cumulative Updates (CU) that have been released since the 2013 family of products first became available, up to the December 2013 CU and January 2014 PU.

In order to determine if SP1 is installed for Office 2013 or a related product, look for the program version in the list of installed programs in the Programs and Features control panel. If SP1 is installed, the version will be 15.0.4569.1506 or higher. Additionally, if you've installed the SP1 update for an MSI product, SP1 will be listed in Installed Updates in that same control panel.

Microsoft has also released SP1 for Exchange Server 2013. SP1 has already been deployed to production mailboxes in customer environments via the Exchange Server Technology Adoption Program (TAP). In addition to including fixes, SP1 provides enhancements to improve the Exchange 2013 experience. These include enhancements in security and compliance, architecture and administration, and user experiences. Visit tMicrosoft's Exchange team blog to learn more about it.