In reality, the markets (in part driven by privately held firms like Getco) have been evolving to a structure that caters to electronic trading, high frequency or otherwise.

FORBES: Out With the Old, In With the New

The structure will be held together with electronic records.

FORBES: Magazine Article

The 1970s saw innovation in financial futures, the 1980s and 1990s in derivatives, and in the following decade innovation was around the structure and ownership of exchanges as they de-mutualized and went from pit trading to electronic trading, a move which brought more participants into the markets.

FORBES: Is There Profit to be Made from Dodd-Frank Legislation?