See the article by Duncan Cameron on rabble.ca here%
and for a detailed summary of the decision read the new Human Rights Bulletin no. 3 at the website of the law firm Cavalluzo Hayes Shilton McIntyre and Cornish here

It is important to note that the Court left openings for governments to still pass legislation that restricts union rights, such as back to work legislation. There is also a danger that union officials and staff will now be more likely to rely on the courts rather than on mobilizing workers - NS.