Yeah confirm its true, they will both wear retro jerseys...

"Many supporters will already be aware that Manchester City
lost one of our own in the tragedy, goalkeeper Frank Swift," the
letter states. "Twenty-two players, staff and journalists also lost
their lives. We ask that all supporters uphold the good name of
Manchester City and respectfully support the commemorations, which
will also be attended by friends and family of the victims,
including Frank Swift's family."
Sir Alex Ferguson's team have been given special permission by the
Premier League to wear a 1950s-style kit, free of logos and squad
names, and the champions will also mark the anniversary on February
6 by holding a service at Old Trafford and unveiling a permanent
exhibition in the newly named Munich Tunnel beneath the South
Stand.
City also have permission to wear a retro strip. A black ribbon
will be sewn into the kit as a mark of respect and City officials,
backed by supporters' groups, will spend the next month trying to
ensure there are none of the Munich chants frequently heard at the
City of Manchester Stadium.
The club have tried similar campaigns in the past with little
success and privately concerns have been expressed that United are
determined to hold a minute's silence instead of following the
modern trend of holding a minute's applause.