Spotted this on Technet just now:
Takes just a second to sort out so worth doing. The key from before 1st May was for Terminal Services and as such wasn't the "proper" key to use.
Technet said:ATTENTION
If you downloaded RTM versions of Office Professional Plus 2010 or Visio Professional 2010 between April 22 and May 1 please obtain a new product key. Your current product key does not unlock full functionality; we apologize for the inconvenience. No additional download required. See the KB article for instructions on how to re-enter a product key. Your key allocation will not be impacted.
Subscribers who obtained product keys after May 1 have the correct keys
Takes just a second to sort out so worth doing. The key from before 1st May was for Terminal Services and as such wasn't the "proper" key to use.