I'm just messing around. I don't know enough to say if it were counterfeit or not. Looks like it has definitely been cleaned and the MM jumped out at me, but I can't say either way. Could have been cleaned to hide other things or distract away from suspect areas. If it is real then I would love to own it... can alway upgrade later on. There is an auction this Saturday and one is being offered. I will be bidding on it.
By no means am I an expert but IMHO, it is a Counterfeit! Below is my observations of the coin. Look at the "E" in WE on the OP's Cent! The center (West to East) bar is shorter than on a genuine 1909-S VDB Cent as all of the bars should be equal length. Also, the upper bar curves upward while the lower bar curves downward when they should be straight. Look at Lincoln's mouth! The mouth line runs West Southwest inward from his' lips, while the mouth line on a genuine 1909-S VDB cent runs due West. Look at the V.D.B. (which I believe is part of the design elements cut into the Master Die when it was produced and not punched into the Working Dies before use)! The V.D.B. on the OP's Cent is a little too far to the East. Also, some of the Lettering in "UNITED" and "OF" of "UNITED STATES OF AMERICA" appear to be tilted (rotated) slightly towards the left. I could be wrong about my observations of the coin but that is how I see it! Frank