This movie is manipulative crap. Apparently the book is really good. I won't be reading it though, because the movie has ruined it forever.
Yes, Hathaway's accent is terrible. Even by the end, I couldn't work out what it was supposed to be. But I'm startled that most reviewers had picked that out as the film's worst sin.
Maybe it's the storytelling conceit that you only see these two one day in every year, but Dex is an unredeemable douchebag and Emma is a doormat. There seems to be nothing romantic about their interaction at all. And the fact that she DIES made me about as angry as that equally idiotic piece of dross City of Angels where the same thing happens. Couple finally unites, only to have one of them smashed into the road. Awesome.