Compared to the Italian version
I found this one implausible, mainly because who in their right mind would ever think Rachel Bilson hotter than Jacinda Barrett? I can see the reverse but not this.
In the Italian version the Michael's character cheats on knockout Giovanna Mezzogiorno but it's more believable because (1) Martina Stella is an uber knockout and (2) she plays the seductress so flawlessly and convincingly, something Rachel Bilson simply fails to do.
Other annoying things about the US version.
The Coldplay song KILLS what would have been a reasonable romance scene.
Zach Braff speaks through his nasal passages, and is an alarmingly ordinary actor.
The misogynous overtones throughout.