Follow this blog on twitter Cajunmcse on Twitter
SP1 went RTM today which means it will be widely available soon. According to the Microsoft server division blog, the service pack will be available to Microsoft's TechNet and MSDN subscribers, as well as to Microsoft volume licensing customers, on Feb. 16, 2011. It will be generally available via the Microsoft Download Center and Windows Update on Feb. 22
You can see the blog and news here: http://blogs.technet.com/b/windowsserver/archive/2011/02/08/windows-server-2008-r2-and-windows-7-sp1-releases-to-manufacturing-today.aspx
New features in SP1 include dynamic memory for Hyper-V VMs and RemoteFX which enables rich desktop content for Virtual Desktop Infrastructure.