Current timeline appears to vary from six months to one or two years, but for some longer, and for a few a lot longer. But the general time line also varies from year to year, some years better than others, some far worse.
In the recent past, especially for those who applied 2010 to 2012, a large number of applications were taking two to three years, and way too many were taking even longer. During that time, the fastest timelines were longer than a year, but there was not a big number taking less than 18 to 20 months.
By the second half of 2013, a much larger percentage of applicants were experiencing faster processing times, and the time line was as low as six months. My application, for example, arrived at Sydney in early July 2013 and I took the oath barely eight months later, very early March 2014. Person sitting next to me at the oath had just applied six months previously.
In the two plus years since (mid 2014 to now) it appears that processing timeline are trending toward improvement, albeit 8 to 12 months appears to be the standard for those who are fortunate enough to experience the faster time line. There are no reliable statistics available for how many are slipping past 18 plus months, but there are indeed a lot of applicants who have had their case pending now for two plus years.
As others have noted, there are some factors which appear to affect how quickly things go for particular applicants. Mostly, however, we have some good clues about what will increase the risk of a longer processing period of time. Mistakes in the application, omissions or inaccuracies in reporting travel history, any prior history of issues like concerns about compliance with the PR Residency Obligation, any history associated with any of numerous consultants known to have facilitated fraud, all are examples. There are others regarding which there is less of a consensus about their impact; for example, my perception is that applying with a minimal margin over the minimum is bound to invite increased scrutiny and thus risk delays. Many think that frequent travel will invite elevated scrutiny and delays, but I also think that reporting no travel at all also invites IRCC to take a closer look. Work or residency status in countries other than Canada and one's home country appears to invite more questions; thus, those who worked in the ME or in the U.S., appear more likely to face delays.
But the practical reality is that there are so many factors it is impossible to identify and enumerate all of them, let alone reliably describe how they influence the process.
Thus, overall, the timeline for the vast majority applying these days appears to be from six months to 24 months, some longer, and how it will go for any particular individual is largely a guess.
