It is a transfer through the corporation of part of the market capitalization owned by existing shareholders. The grant is made to acquire the services of the employee, and presumably has a value equivalent to the cash or other compensation that would have been required to obtain those services--what economists call the opportunity cost of employing those services.
Is it still relevant and effective? I think it can be argued that the G-20 has achieved a number of successes, certainly remains relevant, and many would agree that it is indeed the most appropriate forum given its representation, and as such is well placed to address issues of global economic and financial importance.