the average for us citizens lately seems to be 6 months from submission to decision made. while summer applicants saw quicker processing times, it was not the "norm", and it's really caused some applicants to assume all applications will go that fast.
really US applicants shouldn't be assuming they will get approved before 6 months. to expect it to be less will just lead to disappointment. it's far better to be surprised at a quicker processing time than to get upset it's taking "too long". i am sure applicants from other countries will agree 6 months is considered quick in the grand scheme of things, and US citizens are quite lucky in their processing.
also, it has to be noted in the months since i started keeping track on this forum, there has been a "rotation" of quick processing offices. back in the spring, it was common for syndey and paris to approve applicants in 3 months. now those offices have slowed to almost a complete stop, resulting in overflows to stay in mississauga. it then switched to ottawa, now it's uk and some asian applicants. it's really hard to figure out how CIC does anything, so who knows why some people get approved in 3 months, and others get approved in 6-12. as others have pointed out, it can be as simple as the xth application in queue gets pulled for quick processing or they may be experimenting with a more efficient process.
when i submitted our application, the average time was 8-10 months. after SA, i stopped thinking about the application and *hoped* i'd be in canada for the holidays. while it was very difficult to not obsessively think about it, it was also a pleasant surprise to be approved in half the time. so my advise to all waiting is to relax and stop stressing about how many days it's been. it's important to release the needs for control and having to know what's going on. the truth is once your application is submmited, there is very little control or information shared by CIC, so needing it will only lead to frustration. let it gooooooo, let it gooooo! it will certainly make the process go much faster when the days are not counted and it's accepted there will be months of silence.