Note that you will need to patch SQL Server with the latest cumulative updates for SQL Server 2008 or SQL Server 2005 depending on what version you will be running.  These are as follows :

• SQL Server 2005 SP2 CU3 http://connect.microsoft.com/VisualStudio/Downloads/DownloadDetails.aspx?DownloadID=23806
• SQL Server 2008 SP1 CU2 http://support.microsoft.com/kb/970315
• WCF Hotfix for Windows (KB976462) – To be installed after the SharePoint 2010 Preparation Tool has been run which installs the core prerequisites. http://connect.microsoft.com/VisualStudio/Downloads/DownloadDetails.aspx?DownloadID=23806

Note that Windows 2008 R2, SharePoint 2010 and Exchange 2010 are 64 bit only

The server-packages of JuneCumulative Update for Microsoft Office SharePoint Server 2007 and WindowsSharePoint Services 3.0 are ready for download. KB articles are also avaliable.

Download Information

Windows SharePoint Services3.0 June cumulative update package
http://support.microsoft.com/hotfix/KBHotfix.aspx?kbnum=971538

Office SharePoint Server2007 June cumulative update package
http://support.microsoft.com/hotfix/KBHotfix.aspx?kbnum=971537

Detail Description

Description of the WindowsSharePoint Services 3.0 June cumulative update package
http://support.microsoft.com/kb/971538

Description of the OfficeSharePoint Server 2007 June cumulative update package
http://support.microsoft.com/kb/971537

For information on what's included in the service pack view the Announcing WSS 3.0 and MOSS SP1 article from TechNet. This information will be important from both a business and technical perspective to support installing SP1. The KB "Description of Windows SharePoint Services 3.0 Service Pack 1 and of Windows SharePoint Services Language Pack 3.0 Service Pack 1" in addition is a must read. It includes a link to a list of fixes included in WSS SP1. For Office SharePoint Server 2007 SP1 another KB has been posted with a downloadable Office Servers list of fixes.

Note: For SharePoint Server 2007 environments, WSS 3.0 SP1 should be installed before SharePoint Server 2007 SP1.