Microsoft was quick in putting together a 2010 SP1 VHD as soon as the service pack was released.
This download enables you evaluate Microsoft Exchange Server 2010 SP1 for 180 days. Windows Server 2008 Hyper-V or Windows Server 2008 R2 is required to use this virtual machine. This trial software is intended for evaluation purposes only. There is no product support for this trial.
Login details for the virtual machine.
Download it here