Although Charlie Sheen has finally checked himself into an undisclosed rehab facility, no one knows how seriously he's going to take it until the ratings come in for this week's 'Two and A Half Men.'

"If the ratings go through the roof again, as they did after Charlie's incident in New York, CBS and Charlie will be out again in no time and back to his old ways," warns a close friend of the actor. "However, if the public finally stops rewarding Charlie for his bad behavior, then, and only then, can you expect him to take the situation seriously."