multiparent capability?

I could use this, and may be able to contribute code, but it would need to be for 5.x-1.x as well. If someone good with 6.x-1.x can help with porting, I can sell it better: we'll probably want to migrate to 6.x when module support for it is has solidified (and we're out of demo).

This would make nodes fairly functionally equivalent to taxonomies. Its not hard to imagine wrapper code that made them truly semantically equivalent, which might allow free mixing of node and taxonomy modules and capabilities. (Or it might be ten tons of flax . . . I admit I'm speculating grandly from ignorance of the code, having only just found this module.)

ETA: http://drupal.org/project/nat appears to do this, largely as a side-effect; it uses taxonomy for the parent-child relationships. I'll have to test & compare.

I'm looking at using NH and NAT together - see #335324: Integration with Node Auto Term [NAT] and Glossary

I haven't started playing yet, but here's my thinking so far (possibly use Taxonomy Node instead of NAT?):

NAT: when you create a node (let's call the content-type Topic), it automatically creates a taxonomy term in a given vocabulary (per content type); the term matches the node title. The Topic node is considered a parent of all the nodes tagged with the same-name term, so it isn't actually tagged by that term. Another way to think about it is that NAT lets a Topic node "represent" the same-name term. NAT's Views integration ("Nat: nid") lets you set up a View so when you're on a Topic node, all the children (nodes tagged with the same-name term) can be displayed. NAT also allows the node to be aliased to the tax-term path.

My idea is to use NH to handle the "explicit navigation" as it does so well, coordinating menu/breadcrumbs and URLs. Call this the "spine" of the site. But rather than having to fit a huge number of (visitor contributed) nodes into this explicit structure, users just assign topic terms to their content and it automagically appears as a child of every Topic node in my NH-managed hierarchy.

Note that the Topic nodes can also be tagged with other (not same-name) topic terms, and now they will show up as children of those Topic nodes as well.

Voila! multiple parents. Use your Views to handle further filtering/sorting/grouping as needed - I'm also checking out Node Queue and RelatedContent modules to help with that.

I'm also considering making the Topic nodes Glossary entries, so all content within the user-contributed nodes are automatically tagged with appropriate links to Topic terms, independently of the user's tagging - see also #335324: Integration with Node Auto Term [NAT] and Glossary

I could use this functionality as well. It looks like the database structure would support this straight off, unless there is some funky indexing going on.

me interested too. submitting

This is part of NH 6.x-2.x branch. The *.x-1.x branches are feature stable and bugfix only.