Documentation on $node object is missing

The properties definitely depend on which modules you have enabled... but we could/should probably document the standard/core parts of it. See also #630826: Document which properties are available in user objects..

Basically, we could probably use some overall documentation on $user and $node objects, and maybe some others?

Here is an overview of the node object for Drupal 5 and Drupal 6:
Node object reference

Should this be closed, given that this documentation apparently exists? Should I close it?

The referenced doc is not on api.drupal.org, so no I don't think it should be closed. Probably should be marked as 7.x though.

$user could use some love as well
http://api.drupal.org/api/drupal/developer--globals.php/global/user/6

There's another issue for $user. Let's keep this one focused on $node.

subscribe, also looking for D7 $node reference.

I would suggest the following course of action:

• Document the basic object structure in entity_load(), including the field structure for fieldable entities
• Add a reference to entity_load() to the *_load() functions for the six core entities (node, comment, user, file, taxonomy term, taxonomy vocabulary)
• Add a group for the hook_*_load() for the six entities
• Add a reference to that group to the *_load() functions