1) Shallow catalog - based on WH-word, or other sentence-initial info.

2) Answer (=entity) Type frequency and distribution. Based on CONTEX ontology tags

3) Answer Format frequency and distribution. Attempts to describe structure of answer when the answer may consist of more than one entity; or if the answer must be a narrative type. (definition, reason, compare-and-contrast, etc.)
 
 

Handy references:
4) question-tag hierarchy
5) first stab at answer-type analysis by tag
6) Descending frequency sort of all tags
7) Explanation/justification for each tag