There's an interesting article published in The Pharmaceutical Executive (yes, it does sounds like a nomination for Angus Deayton and Have Got News for You? - I lead a sad life, OK?) Called "The Right Stuff".
The article (available in .pdf format) comments that great businesses are built and not born, and the builders are people. Great businesses need great people. Business success therefore depends on finding the right people and nurturing their leadership potential.
The comments are based on a survey carried out within the pharmaceutical industry, although are not specific to that industry. (The sample size for the survey is a bit questionable however.) The survey examined recruitment and nurturing of leadership qualities, as well as more specific examination of such issues as emotional intelligence (EI) and derailment (when a rising star stops rising).
The end result is something of an endorsement for EI in that whilst IQ can be believed to be static, there is room for development of EI.