He likes to dance and keeps in time.
Does it mean his dance is not old style, but up to current trends?
Other usages:
When speaking of music or dancing, "keeps in time" refers to the rhythm of the music. Someone who keeps good time is always aware of the beat and is able to either sing, dance or play an instrument in perfect rhythm. (There are some folks who love to dance but aren't necessarily very talented at it and are unable to coordinate their steps with the beat of the music.)