Somewhat promising here with AO Scott of the NY Times and rather wickedly funny in his review[as usual].
http://movies.nytimes.com/2011/08/19/mo ... ref=movies
There is this mention which is quite amusing:
"Being British, the two main characters — their names are Emma and Dex, and they are played by Anne Hathaway and Jim Sturgess — identify that square on the calendar as St. Swithin’s Day, which their American Gen-X counterparts may be more likely to know from the lovely, lovelorn Billy Bragg song of the same name.
As far as I could tell, that tune is not heard on the soundtrack, though much else is, including a lush, swooning, deliciously anachronistic orchestral score by Rachel Portman and a handful of period-appropriate numbers.
By the final credits, as a song by Elvis Costello drowns out the snifflings of the audience — late-season allergies? mourning for lost youth? (spoiler redacted?) — the structural principle of the movie may at last become clear. Though it was adapted from a best-selling novel (by David Nicholls, who wrote the screenplay), “One Day” is less a conventional story than a mixtape."
And I do l find his final comment, equally amusing, as well-
"On the other hand, you might cringe to see the film’s wit and delicacy ruined by maudlin excess and wish you could remix the tape to get rid of that song you always hated."
"....there's a merry song that starts in 'I' and ends in 'You', as many famous pop songs do....'