It depends what visa office you apply through. The CIC website gives the average processing times:
http://www.cic.gc.ca/english/information/times/index.asp
I suggest you visit this 2 threads and from there you can at least get some ideas on the processing times, but mind you, its always a case to case basis, not all applications are the same. Ours took 5 months only, my other batchmates are still waiting for their DM's and visas. Goodluck! ;D