I would also like to point out that 15 of the 30 MLB teams have made the playoffs in 2006 and/or 2007.
Sox, Yankees, Guardians, Twins, Tigers, Angels, Athletics, Mets, Phillies, Cardinals, Cubs, Rockies, Padres, Diamondbacks, Dodgers.
I think thats fairly impressive parity.
EDIT: And yes, the Yankees are the only team to make both.