No sooner did news break that Megan Fox had parted ways with "Transformers 3" than the rumor mill started to churn with possible replacements for the displaced 24-year-old actress. Both TheWrap.com and AintItCoolNews.com have published reports from unnamed sources floating names of potential new love interests for Shia LaBeouf, from Gemma Arterton to Bar Refaeli to Zoe Saldana.

So which one is the best fit? Let's run down the list and see.

Gemma Arterton
Pros: The Wrap contends she's the front-runner. Makes sense, in that she's not only drop-dead gorgeous, but has experience with big-budget action flicks. In April, she appeared in "Clash of the Titans," and her starring turn in "Prince of Persia: The Sands of Time" will hit the big screen later this month.

Cons: Blockbuster fatigue. Will she be eager to dive into a third mega-budget production? And will audiences want to keep seeing the same actress in blockbuster after blockbuster?

Bar Refaeli
Pros: There's no doubting the Israeli-born Sports Illustrated swimsuit model has what Bay desires in terms of looks. And perhaps boyfriend Leonardo DiCaprio can give her some acting tips.

Cons: She has next to no experience. Her sole film credit is as the star of a small, upcoming psychological thriller called "Session."

Zoe Saldana
Pros: She's beautiful, a first-rate actress and has no problem kicking ass on the big screen.

Cons: Like Arterton, Saldana already has two big franchises on her résumé in "Avatar" and "Star Trek." "Transformers" producers might be wary to sign up an actress with so many other commitments already on paper.

Miranda Kerr
Pros: She's a Victoria's Secret model. In Bay's book, that might be all the "pro" she needs.

Cons: She makes Refaeli look like a seasoned actress, as she's never acted professionally in her career.

Brooklyn Decker
Pros: The SI cover girl has popped up in episodes of "Ugly Betty," "Royal Pains" and "Chuck." She also is set to appear opposite Jennifer Aniston and Adam Sandler in "Just Go With It." If Bay wants a bikini bombshell with acting experience, Decker might be his best bet.

Cons: Small roles in TV shows and a part in one big-screen film doesn't exactly mean she's ready to step up and star opposite Shia LaBeouf in one of the biggest movie franchises on the planet.

Emmanuelle Chriqui
Pros: The "Entourage" actress can play sultry or sensitive. She's got comedic timing. And she's a vet, having worked in the industry since the mid-'90s. Plus, Chriqui and LaBeouf just kinda look like they're a good match, no?

Cons: What cons? We like this pick. We like it a lot.

Hayden Panettiere
Pros: Now that "Heroes" has been canceled, she has a whole lot of free time. Plus, it doesn't seem like she has any film roles lined up and ready to go. With "Transformers 3" set to start this summer, Panettiere could easily step into Fox's shoes.

Cons: At 20 years old, she might seem a bit young to star opposite the 23-year-old LaBeouf.

Ashley Greene
Pros: After being a supporting player in the "Twilight" films, Greene seems ready for her breakout turn on the big screen. She has name recognition and acting chops and has shown she can remain poised in the face of intense media scrutiny. That last point might be very important to Bay at this stage in the game.

Cons: Will "Transformers 3" wrap before "Breaking Dawn" starts up?

Amber Heard
Pros: The beautiful blond actress might be a welcome departure from Fox. If Bay truly wants an out-with-the-old, in-with-the-new casting choice, Heard would be a fine choice. She's also versatile. Just check out her filmography: "Zombieland, "The Informers" and two upcoming flicks, "The Rum Diary" and "Drive Angry." Lots of different genres equal lots of different skills for the actress.

Cons: It's hard to think of a downside on this one. If she doesn't get the role, it will simply be because Bay and his team decided to go in a different direction.

Vanessa Hudgens
Pros: She has oodles of experience, a girl-next-door charm and no problem negotiating the media spotlight.

Cons: Can she transition from Disney sweetheart to "Transformers" sexpot?

Camilla Belle
Pros: She's a serious actress ("The Ballad of Jack and Rose") who has also done the big-budget blockbuster thing ("10,000 BC"). And of all the names mentioned thus far, she might look the most like Fox.

Cons: Might she look too much like Fox?

Jessica Lowndes
Pros: As evidenced by "90210," she can play edgy. If that's what Bay wants, they should give Lowndes a close look.

Cons: As with Belle, Lowndes might simply look too much like Fox.

Julianne Hough
Pros: America loves Julianne Hough. End of story.

Cons: While she's lined up roles in music-centric flicks like "Burlesque," can she cut it in a straight-up action flick? Will the public accept their "Dancing With the Stars" gal as she flees from some angry robots?

Who do you think should replace Megan Fox in "Transformers 3"? Share your picks in the comments!

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