If Jenny Olsen is a character in the Man of Steel movie, then the next question for fans is if she actually plays a female version of Jimmy Olsen or just a relative of Jimmy Olsen. There has been some speculation that Jenny Olsen could be a sister of Jimmy Olsen, which would leave the door open for Jimmy Olsen to appear in a later Superman movie. However, most speculation points to Jenny Olsen being the version of Jimmy Olsen that will exist in Man of Steel universe.
The character of Jenny Olsen is not technically new, as she previously appeared in Superman #349. In the Superman #349 storyline, Superman returned from a space trip to find out that Mr. Mxyzptlk had turned everyone on Earth into the opposite sex. Lois Lane became Louis Lane, and Jimmy Olsen became Jenny Olsen.
The presence of a pre-existing Superman storyline involving the name Jenny Olsen could indicate one of two things. It’s possible that a prankster uploaded the information to IMDB, and it’s also possible the producers/directors/writers of Man of Steel decided to pay homage to Superman #349 when they decided to cast Jimmy Olsen as a woman.
If Jimmy Olsen has become Jenny Olsen in the Man of Steel, then Superman #349 should start to rise in price as the speculator market becomes aware that it is technically the first appearance of Jenny Olsen in comics. Currently, Superman #349 can easily be found on eBay in the four to five dollar range, but expect that price to start to rise if the change is confirmed.