President Barack Obama did American men a favor. He reminded them it was Valentine's Day. "Let me start with a quick public service announcement for all the gentlemen out there. Today is Valentine's Day," Obama said in a message yesterday. "Do not forget!" he warned,suggesting that he himself could have used a reminder at some point in his relationship with his wife of 19 years,Michelle. "I speak from experience here." "It is important that you remember this," he continued in a preface to remarks about the benefits of a payroll tax cut. "And go big,that's my advice." It was the kind of counsel that might be slightly off message for a president trying to portray himself as fiscally prudent. But on Valentine's Day men are wise to put cost aside. And,no,the president did not forget his own obligation. At 2:39 p.m.,he delivered a personal greeting on Twitter: "Hey,(at)MichelleObama: Happy Valentine's Day. -bo" No word on how big he went.