I am a MS1 at OHSU. They are pretty slow. They will string you along throughout the spring if you are on the waiting list. If you are flat-out accepted (or rejected, for that matter) you will know before May. I was placed on the waiting list last year and I finally heard around the beginning of June that I had been accepted. The nice thing is that they tell you your place on the list. If you do make the list they routinely accept up to number 40.