Begun in 1987, the "Pork. The Other White Meat" ad campaign hoped to raise America's pork consumption, which had been in decline for several years. Due to poultry's increase in popularity as a health food, the National Pork Board thought they should try to even things out by creating a new demand for pork.

The National Pork Board successfully projected the image that pork is a "delicious break from the boring meal routine," and it was now competing with other "white meats," such as poultry and fish, rather than its traditional "red meat" rival, beef.

Indeed, the campaign was so successful that "Pork. The Other White Meat" was ranked among the top five ad slogans of the 1990s, right up there with "Beef, It's What's For Dinner." It brought about higher quality cuts of pork, with a notably wide decrease in the amount of fat found on the average cut.

Recently, the campaign has turned into a blanket for several other pork-related slogans, such as "I Scream, You Scream, We All Scream For Pork Loin"; "Gentlemen, Start Your Pork Chops"; "One Potato Two Potato Three Potato Pork"; and "Give My Regards To Pork Chops," the latter of which only appearing in New York City's Times Square. (Due to its proximity to Broadway. You know, "Give My Regards To Broadway," "Give My Regards To Pork Chops"... ah, fuggedabodit.) As you can see, these ads have become a part of the recent (so-called) "surrealism" movement in advertising, when really, it's little more than randomness. Oh, well, give my regards to pork chops.

Sources:
http://www.otherwhitemeat.com/