Last fall, Obama’s campaign commercials touted his endorsement from iconic investor Warren Buffett.

In his speeches, he referred to “my friend Warren Buffett” and said, “Warren Buffett is one of those people that I listen to.” In the third presidential debate, Obama agreed with McCain’s suggestion that “Warren would make a pretty good choice” for Treasury Secretary.

Slate called him “perhaps Obama’s most powerful validator.”

Today, Buffett told CNBC that he had spoken to Obama once since he’s been in office. Buffett’s still positive on Obama, but disagreements on several issues have cropped up since the inauguration — whether the president should focus more time and energy on the economy, the type of spending that was in the stimulus, card check, the economic forecast for the coming year, the administration’s push for the more controversial aspects of their agenda, etc. …