The SP1 has been released. You can download it here. (Release Notes)

Some changes to make the deployment easier:

• Slipstream – You are now able to integrate the base installation with service packs (or Hotfixes) and install in a single step.
• Service Pack Uninstall – You are now able to uninstall only the Service Pack (without removing the whole instance)
• Report Builder 2.0 Click Once capability