This is no help at all. It states the obvious, and it says what's true about federal policy toward all the states. The feds are not prosecuting the small-time user. The question in Colorado and Washington state is about how the state is supposed to manage the situation, given the conflict with federal law. They've asked for a federal response, and this gives them absolutely no new information.
He does say a bit more...
"This is a tough problem, because Congress has not yet changed the law.... I head up the executive branch; we're supposed to be carrying out laws. And so what we're going to need to have is a conversation about, How do you reconcile a federal law that still says marijuana is a federal offense and state laws that say that it's legal?"... but that's restating the question, not answering it.
What we're going to need to have is a conversation about... that's so annoying. Give an answer!