Sorry, I should have qualified. I was going on the general rule that SJ is larger as per the last 2001 Census data from -
The population info for the 2006 census is only released March 13, 2007.
Assuming the same rates of growth seen in between the 96 and 01 censuses, the populations of the two cities should now look something like this -
122 082 - Moncton CA (3.7% growth from 2001 for the CA)
119 732 - Saint CMA (2.4% decline from from 2001 for the CMA)
That, however, wouldn't be accurate as Saint John has done better from 2001 to 2006 than it did from 1996 to 2001 (I am sure much, or a considerable portion, of population loss in that census was due to the end of Shipbuilding and the subsequent departure of several hundred families).
I checked out Enterprise Saint John (http://www.enterprisesj.com/en/index.php?id=14
- this is where the Wikipedia info is from) and they show what HalifaxMTL666 said -
126,600 Saint John Census Metropolitan Area (CMA)
Regional catchment and commuter population of 175,000
Those are 2005 numbers and they also make sense - Saint John has a more extensive and farflung network of suburbs and de facto bedroom communities so actual changes in population are not accurately reflected by simply examining the CMA.
The Moncton CA is increasingly similar in size and growing faster than the SJ CMA but I don't believe that it has attracted the 9,000 people it would have needed to outrank the SJ CMA since the last census. Even if this were to occur, SJ would still have a considerably larger commuter basin.
Additionally, The Saint John CMA would probably post the strongest growth in the province if the second refinery goes ahead and the LNG plant is a success.