From the same site:
I assure you, the new administration's more tolerant approach to medical marijuana didn't happen because Obama is particularly concerned about the plight of seriously ill patients caught in the drug war's indiscriminate crossfire. It happened because it's no longer politically viable to overturn the will of voters in the war on marijuana.
Sure, we'll continue to hear the drug czar whining from time to time about the perils of legalization, but if Californians decide to go through with it, don't expect a federal occupation in the streets of Oaksterdam. Obama's base is decidedly supportive of marijuana reform, thus he has nothing to gain and a considerable hassle to endure should he be foolish enough to stand between Californians and their cannabis.