Market Markers: people on Wall street that match up sells with buys. Often pertained to as Market Manipulators, since they tend to ARTIFICALLY CONTROL PRICE MOVEMENT for alleged alterior motives.
do a goolge search for more clarification.
Movement towards purely electronic trading to avoid mistakes, and preference towards the BIG WIGS!
Yep, it's market maker like Oilbaron said. People with REALLY deep pockets. Could be reps of online investing firms like E-trade, could be huge banks like Citicorp that may represent institutional buying or could be hedge funds...
That's my understanding of the term. People with big money that are in position to significantly impact market activity.