No, we are not
We are considering an upgrade because we need to refresh a few of our oldest servers.
The primary benefits that I see from the upgrade are IPv6, RODC, and SMB2. Hyper-V is not at the top of the list, but I would like to compare it to our VMware environment.
Yes, we are planning for an upgrade to windows server 2008 R2. We have already done it in our test environment. Its fabulous. There are many more benefits it can provide you like Hyper-V live migration, Recycle bin feature for Active Directory, Branch office cache. Then there is another new feature with Windows server 2008 R2 i.e. DNSSec. You can secure your DNS Server with the option of DNSSec. This is one of the nice feature I found with Windows server 2008 R2.