A new Transformers: Dark of the Moon teaser poster featuring Optimus Prime was discovered by Joblo, who report that this particular character 1-sheet was featured at the 2010 Licensing International Expo. And, while it is an officially licensed image, it may not be intended for theaters but for retailers. Especially since it has omitted "Dark of the Moon" from its title. You can check out the image below:

Transformers: Dark of the Moon Poster