Microsoft has released the Sharepoint 2010 products Service Pack 1 on June 28.
The Service pack can be downloaded from the Update Center for Microsoft Office.
Microsoft recommends installing the June 2011 Cumulative Update immediately after the installation of Service Pack 1. The update includes fixes that did not make it into Service Pack 1.
For more information about the installation of Sharepoint 2010 Service Pack 1 you should check out the Microsoft Sharepoint Team Blog.
Additional Resources
Description of new functionality in Sharepoint 2010 Service Pack 1 from the Microsoft Sharepoint Team Blog
Sharepoint 2010 Service Pack 1 Release Notes