McMaster's TA union, CUPE 3906 Unit 1, has a collective agreement which expires in 2009. (source)
However, CUPE 3906 Unit 2, which represents McMaster's contract faculty members, recently negotiated a collective agreement to expire in 2010, and the contract length was an issue in bargaining.
I'm currently looking at the details of bargaining at Mac to compare them with the current situation at Guelph. I'll post something about that in a couple of days.