Vocabulary

criticality: 
Moderate
Drupal7: 
Open
This happened to: 

User expected to see categories and tags as hard-coded choices - not vocabularies. Didn't like the terminology, worked out the concept after creating a vocabulary though.

Implications: 

Taxonomy interface presents a huge wall of text describing what it does, isn't very encouraging for getting started.

Solution: 
Shorter help text, more encouragement to get started creating a vocabulary since it's easier to get the hang of things once it's started.