### Internal Storage Layer
* **[stable]** The internal storage layer for kubernetes cluster state has been updated to use etcd v3 by default. Existing clusters will have to plan for a data migration window. ([docs](https://kubernetes.io/docs/tasks/administer-cluster/upgrade-1-6/))([kubernetes/features#44](https://github.com/kubernetes/enhancements/issues/44))

### kubeadm

* Support both JSON and YAML for scheduler configuration. ([#75857](https://github.com/kubernetes/kubernetes/pull/75857), [@danielqsj](https://github.com/danielqsj))
* kubeadm: fix "upgrade plan" not defaulting to a "stable" version if no version argument is passed ([#75900](https://github.com/kubernetes/kubernetes/pull/75900), [@neolit123](https://github.com/neolit123))

* GCE Windows nodes will rely solely on kubernetes and kube-proxy (and not the GCE agent) for network address management. ([#75855](https://github.com/kubernetes/kubernetes/pull/75855), [@pjh](https://github.com/pjh))
* kubeadm: fix "upgrade plan" not defaulting to a "stable" version if no version argument is passed ([#75900](https://github.com/kubernetes/kubernetes/pull/75900), [@neolit123](https://github.com/neolit123))

### OpenStack

SIG-OpenStack updated the OpenStack provider to use newer APIs, consolidated community code into one repository, engaged with the Cloud Provider Working Group to have a consistent plan for moving provider code into individual repositories, improved testing of provider code, and strengthened ties with the OpenStack developer community.

### API-machinery