If it's crap ... We'll tell you
In the remake, which is to be directed by James Sheridan, Gyllenhaal would play the younger brother and Maguire the older one.
Assuming an audience can tell them two of them apart for an entire movie, I suppose this could start a trend of more "Separated at Birth" movies. Maybe pairing Helen Hunt/ Leelee Sobieski, Tommy Lee Jone/ Josh Harnett, Johnny Depp/ Skeet Ulrich, Chris Klien/ Keanu Reeves, Alan Cumming/ PeeWee Herman, etc.
You know, all the greats.