The testing phase of all the Office 2013 products have ended and reached the RTM status, which is the version that is ready to ship to customers. This also includes the server family of the Office products such as Exchange, SharePoint and Lync.
General availability is planned for the first quarter of 2013 (most likely the last week of January or the first week of February). When you purchase Office 2010 on or after October 19, you’ll receive Office 2013 for free when it becomes available.
When you bought a Windows RT device such a Microsoft Surface, which will become available on October 26, it will still include a preview version of Office 2013.
MSDN and TechNet subscribers as well as Volume Licensing customers with Software Assurance will be able to download the Office 2013 applications as well as the server products by mid-November.
Office 365 subscribers will see their server-side services being updated between November and February.