In return for Wisniewski, the Islanders received a compensatory second-round pick in 2011 and a conditional fifth-rounder in 2012.
Wisniewski, 26, isn't expected to join his new club until Wednesday in Tampa Bay, and so will miss the Habs' Tuesday game at Washington.
The defenseman has scored three goals and notched 18 assists in 32 games this season. He has 20 goals and 98 helpers in 286 career regular-season games with Chicago, Anaheim and the Islanders.
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