Microsoft has released Windows 7 and Server 2008 R2 SP1 RTM to public:
We have already told you that SP1 is a joint release for both Windows Server 2008 R2 and Windows 7. SP1 doesn't contain any new features that are specific to Windows 7 itself. For Windows 7, SP1 is simply a combination of updates already available through Windows Update and additional hotfixes based on feedback by customers and partners.
SP1 for Windows Server 2008 R2 contains 2 new features: Dynamic memory and RemoteFX.
If you don't want to waste your time in looking for the download links, here are the direct download links for SP1 RTM:
Download SP1 RTM EXE (32-bit) (537.809 MB)
Download SP1 RTM EXE (64-bit) (903.196 MB)
Download SP1 RTM ISO (32-bit & 64-bit) (1953.3 MB)