Nice "blog"; one post. The image would need a larger surface than the moon to be visible from earth, either that or extremely detailed.
First you have to tell us that what it is and by the way it is a nice way to increase traffic!! keep it up.
I guess if this sort of thing was real it'd seem to only appeal to the younger generation as alot of people with vision problems probably won't be able to see what the moon was saying. Sheesh, how powerful would that laser have to be? lol - and what would happen to the object that accidentally crossed it's paths? - boom?
The aliens can probably already see every bit of advertising already happening on earth with their uber technology. No need for the moon to tell them.