Release Notes, Austin
The Austin release is the first OpenStack release which combines the Swift and Nova projects.
What's New in OpenStack
These sections contain what we expect will be implemented in time for the October 21 release, but be aware that these may change.
Xen Hypervisor Support
In addition to KVM, user-mode-linux and Xen Server, Nova supports Xen classic in the Austin release by adding a libvirt domain xml template with a xen option.
Security groups implementation
EC2 and Eucalyptus API's both contain a firewalling concept known as security groups. People migrating from EC2 (or Eucalyptus) may be using security groups as part of their security model. To use this feature, look for a filter in libvirt for each security group. Once the last instance owned by a given user is removed from a node, the filter is undefined (removed).