As far as the article says, nothing has actually been effected yet; this is just the PM confirming his intention to legalize marijuana.
If his party holds the majority in the Parliament and they're all on the same page regarding this issue, I say it's already in the bag and it's just a matter of a few formalities.
I know some people already going into business on the assumption that it will pass. I wouldn't be surprised. Canada could use the income.