Thanks guys.. :)
I am guessing the wait period varies depending upon the visa availabilty per respective country. And I also think they are now processing all cases those were filled in August 2013.
You guys can check the processing times in USCIS website and see the cases that are being processed in your respective field offices. For instance, processing times for "Newark, NJ" field office for I-485 is April 2, 2013 as of now.
However,if I were you, I would schedule an infopass appointment if I wouldnt get any update after until 4 weeks of interview.
Good luck guys !!