Synonymous with the commonly used phrase, "What's up"? Used by one who is looking to find an agenda of recent events.
The phrase "What's crack-a-lackin'?" originated in ghettos, and was used by thugs and gangsters to find out the news about any recent crimes committed in the area ('crack-a-lack' is derived from sound a gun makes when fired).
Pajama casual is a term used when working from home and preparing for a video conference. All business above the waist and your pajama pants down below.