The website says: "The tables below indicate application processing times at Canadian visa offices"
Based on the wording, it appears that after Ottawa receives application, it takes 29 months.
My take is, Total processing time = 29months + no. of months passed between intial application filing and sending application to Buffalo/ottawa
So in my case, I inital filed in May'10 and then sent docs to Buffalo in Dec '10. Thats 7 months months passed between intial application filing and sending application to Buffalo/ottawa. Total processing time = 29 + 7 = 36 (3 yrs)
In theory, I should get PR by April 2013, but I am still waiting for Medicals ;D