No, the visiting Pittsburgh Penguins are not the best team in the NHL. They are the defending Stanley Cup champions, though. Currently in third place in the Metropolitan Division, the Penguins trail front-runner Washington by seven points and second-place Columbus by three points at this writing.
However, the Penguins do lead the league in scoring with 3.55 goals per game (the Blues are ranked 11th at 2.84 goals per game), ably led by Sidney Crosby (28 goals, 56 points), Evgeni Malkin (22 goals, 54 points), Phil Kessel (15 goals, 47 points), Conor Sheary (17 goals, 35 points) and defenseman Justin Schultz (8 goals, 35 points).