Something that seems to be absent from the otherwise great new features for Windows Azure (announced on June 7th), is the ability to define distributed caches for the reserv
This scenario is not supported as of today by Windows Azure Caching (Preview). Thanks for the feedback. I will take this up to the appropriate folks in our team to consider the same for future releases.
As mentioned by Jason and Win, for now you can use Windows Azure Shared Caching. Though you are right that it is limited in Size and has a quota system.