It's unclear what the immediate fallout of the vote will be. The recent 52-day winter transit strike has gone to arbitration, with the settlement expected soon, so there shouldn't be another transit strike until that contract (however long it turns out to be) expires. At that point, there will obviously be negotiations, with the possibility of a resolution or an agreement to go to arbitration before a strike would occur. That's all speculation at this point, though.
In the long-term, the decision could negatively impact the city's standing with labour unions, as reported last month. In the Ottawa Sun, though, OC Transpo general manager Alain Mercier took an optimistic outlook, stating that "This is a vote of confidence in our ability to move forward together." Innes Ward councillor Rainer Bloess, though, told 580 CFRA that he was "disappointed" with the no-vote, believing that it "could have given reassurance to the residents of Ottawa."
For mainstream media coverage of the vote: