Spent some time over the last week on openstack, Its written in Python, so its very easy for troubleshooting during installation or for daily maintenance. I have deployed eucalyptus for clients demo purpose, its really bad from what I can say. The whole java stack is too complicated. Back to openstack, there has something interesting through my experience.
1 Its written in Python, so its a big advantage over eucalyptus to me.
2 Easy to deploy, you can even install it inside a vm, I installed it with virtualbox.
3 Supports sorts of virtualization technologies, like kvm, qemu, xen, hyperV, even UML being supported.
4 Totally modulized architecture, you can easily add new function.
5 Fully open source, but not eucalyptus. :)
