An article in in today's USA Today heralds the fiftieth anniversary of Mad Magazine and spreads a couple nuggets of misinformation. Here's a link to the whole article and here's a quote that I might as well correct here…
In 1955, MAD transformed itself into a magazine to avoid the sanitized Comics Code Authority, which publishers formed under pressure from Congress.
Not true. MAD became a magazine because Harvey Kurtzman — its founder, editor and, at that point, sole writer — wanted to get into slick magazines. Kurtzman had repeatedly suggested that MAD stop being a comic book and become one. He was embarrassed by the image that comics had at the time and feared that censorship — and perhaps the demise of the industry — were in the offing. So when he received an offer to work for Pageant Magazine, he told MAD's publisher, William Gaines, he wanted to accept it. Gaines then believed that Kurtzman was irreplaceable and offered to take him up on his suggestion to transform MAD. This was done.
It would seem logical to assume the change was made because of the Code, especially since it occurred the same month that Gaines began (reluctantly) submitting the rest of his line to the Comics Code Authority. It might also be logical to presume that Gaines was equally concerned about the future of comic books but, to his dying day, he insisted that neither was the case. He said he'd changed MAD to keep Kurtzman and that, at the time, he thought the Code would work for him. (One of the books he began submitting to the Code Administrator was Panic, his own imitation of Mad.)
Just to tie up the loose ends of this story: A few months later, Kurtzman demanded 51% ownership of MAD. Some say he did this because he couldn't stand having Gaines controlling his work. Others say he wanted to accept an offer from Hugh Hefner and was looking for a way to sever his relationship with Gaines. Either way, the end result was that Kurtzman went to work for Hef, and Gaines found out that Kurtzman was replaceable.