The word on the mean streets of Rumoursville town is that Microsoft is going to lift the licensing restriction where currently software is licensed to a physical device.
Why? With technologies such as VMotion and XenMotion, a VM is moved around a farm automatically to where it can make the best use of available resources such as CPU and memory.
With Microsoft products you are required to license all the physical machines that the software is likely to run on, this isn't just Windows but SQL Server, Exchange, Biztalk etc. If it does move to another physical machine by rights it's going to be another 90 days before you can move the software again. A nightmare when in reality you are only using it once in a VM.
So a costly exercise? Potentially but in reality it doesn't happen. Infact what does happen is that other vendors are chosen instead and the migration from Microsoft software starts.
I'm hoping the change in licensing will also help in cold & warm standby DR (Disaster Recovery) scenarios when a license is transfer with the VM via things like Symantec Veritas Netbackup solution.
This rumour is unconfirmed so don't shoot me if it doesn't happen. However it would be an extremely popular move on Microsoft part if they did this.
Microsoft is been behind in matters of VM, it's time for them to catch up and plug a hole that is making them lose out.