J.Lo & Boy Toy Yacht Si!

12/30/2011 2:30 PM PST

Jennifer Lopez & Boy Toy Casper Smart -- Yacht Si!

Boy toy extraordinaire Casper Smart is really cruising into Jennifer Lopez's life ... and rode around on a yacht with the pop icon and her two kids in Miami on Friday.

For J.Lo, 2012 is all about out with the old and in with the new ... arm candy.