randhawa13, you will gain nothing from going into litigation with immigration. They can change the rules any time they want to. If they make a new immigration class which is faster, then it is up to you to follow the changes and apply for that class if you qualify.
If you had been following changes in immigration law while waiting for your PR, you would have known in November 2008 when the rule change was published and could have applied again at that point and probably would have had your immigration already. Instead you waited for your old application to get processed. Eventually it should come through but none of you should imagine that you have any claim against immigration because you chose to wait. Sure you can go into litigation but you are only wasting your time, money and energy. Nothing will come of it.
shanmugam, right now, your processing should be close to complete on the old application. It is a question if it would be worth it for you now to apply again under the new rules. I am sure your agency would be happy to have your money to process your new application under fast-track. Nobody can promise you that it will only take 6 months but that is indeed the average processing time if you look at http://www.cic.gc.ca/english/information/times/international/02b-skilled-fed.asp#asia
The processing time for the old applications can be seen here: http://www.cic.gc.ca/english/information/times/international/02a-skilled-fed.asp#asia and as you see, the average is 64 months or 5.5 years and 80% of cases completed in 74 months or a bit over 6 years.