In January 2010, Fox announced that Simon Cowell would be leaving American Idol to serve as judge and executive producer for the U.S. version of The X Factor, a reality singing competition created by Cowell for the UK, which had proven enormously successful overseas and in various incarnations all over the world since its 2004 debut. For a long time Cowell was the only confirmed talent for the fall debut, until just a few weeks ago, when producer Antonio "L.A." Reid was also confirmed for the panel. But assuming that the show sticks with its four-judge format, that still leaves two seats—as well as at least one hosting slot—unfilled.

As for who will eventually be occupying those remaining roles, it seems like every few days there's a new name being floated, only to be debunked a couple days later. Some are likely floated by the artists themselves, to get their names in the paper; some are undoubtedly the work of the X Factor's PR team, anxious to grab mind-share during the new season of American Idol; some are old-fashioned tabloid fiction. How to keep track of the deluge of rumors and conjecture? Try this handy X Factor gossip timeline, a chronology of who could, might, and definitely won't be involved with show come autumn.

September 1, 2010: The Mirror reports that Katy Perry has been offered a judging role on the show, possibly to the tune of $340,000 an episode. "Simon wants to get the judging names signed, sealed and announced within six weeks," a source tells the Mirror. "He wants at least one massive American star, someone who is known globally, plus one Brit and at least one authoritative male."

September 17: The Daily Mail reports that U.K. judge Cheryl Cole, ex of girl-group Girls Aloud, will likely be joining Simon on X Factor. "‘When Cheryl goes to America she will also launch her music career there too. It’s the next part of her big plan," a show source tells the Mail. The article also mentions Nicole Scherzinger, Katy Perry and Nick Cannon as other potential judge candidates.

December 5: DigitalSpy reports that Zac Efron and Vanessa Hudgens are being considered as co-hosts of the show. "Dermot will be completely distraught," a source tells DS about U.K. host Dermot O'Leary. "He spent months in America lobbying to get this job...But he can't compete with Zac and Vanessa. They are two of the biggest stars in the States and will make American X Factor the biggest show in the world."

December 6: Gossip Cop debunks the rumor of Zac and Vanessa being brought on to host the show. GC cites a rep for Hudgens telling them that reports of the High School Musical co-stars being courted by X Factor are "not true."

January 9, 2011: The Mirror reports that Simon has signed Will Smith to judge on the show. "Simon thinks Will and Cheryl [Cole] will be a brilliant ­formula," a source says. "He’s one of the biggest names in America, and considered to be a talented musician as well as actor."

January 11: debunks rumors of Will Smith's involvement with X Factor, saying that there is "no truth" to the story.

January 12: Contact Music reports that ex-Destiny's Child member Kelly Rowland, who played a mentor on the 2010 X Factor: Australia, is very interested in becoming a judge on the U.S. version. "The X Factor is an amazing show and Simon knows that all he has to do is call me," says Kelly. "I love Simon because he's so honest. When I watch it, everything he says I agree with."

January 26: MisForMusic reports that Simon has approached Christina Aguilera to be a judge on the show. "Although Simon is desperate for Cheryl to join him on the judging panel, bosses just aren’t convinced," a source tells MFM. "Christina is the one all bosses are agreed on. She has it all; looks, talent and she isn't afraid to speak her mind." 

February 10: Closer magazine reports that ex-Spice Girl Mel B. has interest in joining the show's judging panel. "I’d love to be a judge on The X Factor," says Mel. "I think it’s a great show...I’ve also met Cheryl Cole—she’s lovely.”

March 4: Simon appears on Access Hollywood to discuss potential judges. Says that there have been talks with Nicole Scherzinger, Mariah Carey and Paula Abdul, but nixes Christina Aguilera, Katy Perry and Elton John. ("He's so grumpy nowadays!") Says that George Michael is interested, but doesn't know yet if he wants Michael for the spot.

March 16: Deadline reports that Enrique Iglesias is "being courted" to be the host of X Factor. However, reporter Nellie Andreeva says that she hears Enrique "may be more open to a judging than hosting gig."

March 19: The New York Post reports that Nicki Minaj is in talks with Simon Cowell and Fox about being a judge on the show, though an X Factor rep calls the report "early speculation."Also, Celebuzz reports that Taylor Momsen is being considered as a co-host for the show, citing her "hip, young and edgy" qualifications for the position.

March 21: confirms that Mariah Carey has "politely declined" the judge position, citing her pregnancy and work on her new album as reasons why.

March 22: The Mirror reports that Nicole Scherzinger has been asked to be the host and presenter of the show. "Nicole’s had screen tests and is a natural in front of the camera," a source tells them. "As an established singer, both as a solo artist and in a group, Nicole will be great with the contestants and knows what she is talking about."

March 24: Simon confirms to Entertainment Tonight that Paula Abdul is "still in the mix," going to say that "[Paula] definitely has my vote. I hate to admit this but I actually miss working with her. When I was working with her at times, I actually wanted to kill her, she was the most annoying person. And then I'd miss her, and I think she was the same." Also, a TMZ source reports that Nicki Minaj has "nothing going on" with X Factor.

March 28: Jessica Simpson tells Women's Wear Daily that she has been approached to be a judge on X Factor. "I think it would be a lot of fun," says Simpson. "To be a mentor for up-and-coming artists is right up my alley... I love watching people’s dreams come true."

April 3rd: Digital Spy reports that Snoop Dogg turned down a judging role on the show. "They asked me to do that, but I don't think that's for me," says Snoop. "I wouldn't mind going on the show as a mentor, but not as far as a judge."

April 4: L.A. Reid (apparently) confirms Cheryl Cole as the third judge on the show, but says that he does not yet know who the fourth judge will be. Perez Hilton also reports that Rihanna has been asked to join, saying that Simon "wants his panel of judges for the U.S. series to be BIG."

April 5: Demi Lovato becomes the latest name tied to the judging role, when Perez Hilton reports that Lovato has met with Fox about the role, and that according to an inside source, "she would love to do it."

That about brings us up to date. But who knows what the future may hold for X Factor gossip? By this time next week, we wouldn't be surprised if Lil B and Patrice Wilson occupied the last two judging slots, with Justin Bieber's swag coach hosting.