Don't know if I count because I got wait listed at U of T? I am still missing a half course prerequisite for U of T, so I don't know if that was taken into consideration. My reference letters were strong, so I don't think it has anything to do with that (for me at least).
However, I do know of one girl (the only other person I know in real life who applied to SLP this round) who was accepted to U of T (and got OGS!) and was also accepted to McGill. She was wait listed at Western, but she also has lots of life experience and just SLP experience in general. She decided on McGill.
I think it is really difficult to say in general why or why not someone is accepted at one school and not another. Different people are on each committee obviously, so only they really know why one applicant is selected over another.