RedHat managed to package the Integration Service drivers into RHEL 6.4 which essentially is the base of CentOS 6.4. So, from now on the much required drivers are bundled in the installation source.
There are no major changes in the drivers, though. Network status is still degraded and a hint of upgrading the drivers is there. It seems to be a mystery to everybody how to do the upgrade.
The list of integration services is unchanged:
Operating system shutdown
Backup (volume snapshot)
This article in Microsoft's social network describes the changes. Looks like Dynamic Memory (ballooning) is the only new feature. That wasn't even in the RHEL 6.4 beta, but they pushed it into final release.
Does your opensuse 12.3 machine show the network as degraded? I understood that the integration services were built in to this release, but mine show as degraded and I've no clue how to upgrade them from the integration disk.
Sorry, don't know the answer to that one. My OpenSuse is a physical laptop.
However, I have one Arch Linux running on a Windows 8 Hyper-V, and it shows the network status as degraded.
The issue must be with the kernel module providing the network services. It was originally written by Microsoft and my thinking is that they implemented the minimum possible subset to get the thing working.