There's a new update of Maven support (version 3.1.2) on NetBeans stable update center since yesterday. You are encouraged to upgrade as it fixes a few critical issues found in the integration and the Maven embedder that is used. One pom.xml editing enhancement is added.
When editing your pom.xml file, you get the regular xml file navigation panel. That one is provided for any xml file. it shows you the structure of the currently edited xml file in a tree.
The newly added navigator panel will show you the inheritance of your current pom file. That means the artifactId + version of the current file, it's parent POM's artifactId + version and so on, all the way back to the root company or project POM. it will also denote if the parent is accessible in the sources or is being retrieved from the repository. That happens when your project is using an already released version of the parent pom and is not depending on the current version in the sources or when the source is not accessible for some other reason. The editable parent POMs can be quickly opened by double clicking on the node.