Currently:

• All over the place
• Arguments typically correspond to the arguments used in core Query classes (post_status, etc.)

Proposed:

• Post:
  • author (int)
  • search (string)
  • status (string)
  • before
  • after
  • modified_before
  • modified_after
  • page (int)
  • per_page (int)
• User:
  • search (string)
  • page (int)
  • per_page (int)
  • order (asc|desc)
  • orderby (?)
• Comment:
  • post (int)
• Term:
  • search (string)
  • page (int)
  • per_page (int)
• Look into arguments behind design of WP_Date_Query and ensure we’re not reinventing the wheel