As usual, the snopes.com site puts the picture in context and presents a balanced view:
"The photograph displayed above is a genuine picture of a can of Diet Pepsi manufactured in Dubai by Pepsi Arabia (and available, among other markets, to U.S. troops serving in Afghanistan. However, the illustration on the can doesn't appear to possess much more than passing resemblance to the scene of the 9/11 attacks in New York City, so the claim that it demonstrates some intentional disrespect on the part of Pepsi Arabia is questionable.
The depicted scene features a road leading to a city skyline which has two similar (but not identical) tall buildings, with other shorter buildings between them in the foreground, and an airplane flying above (not within) the skyline. All in all, it seems to be nothing more than a generic representation of a big city, with nothing specific tying it to the 9/11 attacks other than its inclusion of ordinary images of skyscrapers and an airplane. This can may be one of seven special designs created by the Dubai Refreshments Company, intended to represent the Dubai skyline:
The 7 Pepsi Can designs include; Abu Dhabi's famous seafront featuring Emirates Palace, Dubai's skyline featuring the tallest building in the world, Burj Khalifa. Sharjah's design is of the traditional Old Souk, Umm Al Quwain is of the iconic horse roundabout, while Fujairah's Can features the bronze dallah statue. Ajman's design portrays the splendid museum, as well as Ras Al Khaimah's iconic dhow and castle imagery.
Consumers have at other times perceived unusual or even offensive messages in innocuous graphics. In 2007, the label on AriZona's Southern Style Sweet Tea drew criticism for purportedly celebrating slavery via an image which some interpreted as one of a black "mammy" standing in the driveway of a plantation house owned by a white couple. Similarly, there were those who saw Bonnie and Clyde driving past the Treasury building on the old U.S. $10 bill.
They have also previously "found" 9/11 images in other products and advertisements. In 2002, Starbucks chose to remove from its stores a poster touting its TazoCitrus drinks because there were those who interpreted its image of a dragonfly's approaching two frosty drinks as reminiscent of the attack on the World Trade Center towers."
More US paranoia, it seems to me. Apologies to those Americans who don't go off half-cocked imagining that all the whole world thinks about is insulting or attacking them. Unfortunately there are enough of them to give all of you a bad name.