Metal Map v0.2
(click image for full version)
Produced by parsing Wikipedia pages for links in the same sentence as "influence" and "inspire", and recursing over those containing "metal" and "genre" or "band". Start point is "Death Metal". Edges are undirected as yet, due to the difficulty of parsing variants on "influences" and "influenced by" etc, but indicate that one node is at least related to another.
The nodes are numbered according to this key.
The connectivity displays scale-free structure:
but that's not surprising given the fundamental architecture it's built on - the web's scale-free topology has been known for a while. A more rigorous and complete influence listing would be required to ensure that this isn't an artefact of the sourcing.