This is well and good, but the process is not efficient enough to deal with the sheer volume of leaks in a timely manner.

You seem to imply that anything that can be leaked should be leaked. There is no morality in haphazardly leaking any and all classified information. This is precisely why established news organizations are effective. They have the will to actually vet classified information for things that would count as whistleblowing. Wikileaks has no such motivation.