http://www.businessspectator.com.au/bs.nsf/Article/Elmer-Funke-Ku...

http://www.businessspectator.com.au/bs.nsf/Article/Elmer-Funke-Kupper-ASX-Chi-X-dark-pools-high-frequ-pd20120531-UT7R5?OpenDocument&src=sph

A bit of a heavy read but the gist of it is that " ... there is a view that their growing levels of activity means securities markets are increasingly markets that favour traders rather than investors and some sophisticated institutions rather than traditional institutional and retail investors"

My view that in practice such markets and assoicated derivatives are going to stop the market functioning as a place to raise capital.