In Eclipse Helios I have the nice feature of a dependency graph inside the maven pom editor.
This has been removed from m2e 1.0 (previously it was available if you selected 'show advanced editors', but that option is now gone too). The developers behind it have stated that the dependency graph never worked that well with more than a handful of dependencies and the dependency hierarchy view works better anyway.
Here is one of the messages from m2e-users about this:
http://dev.eclipse.org/mhonarc/lists/m2e-users/msg00769.html
The Dependency graph is still available! At least in Indigo and Helios-SR2 you can activate the graph in the Eclipse settings: Maven - POM Editor - Show advanced tabs in the POM editor
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