Promotions are a way to drive "sales" and offer an incentive to consumers to buy when they were not necessarily planning to do so.
In previous years, some of AC's promos offered additional AQM and/or decent bonus Aeroplan miles (non-AQM).
If the current promotion seems less valuable to some as compared to previous years, it is possible that AC is making enough money and filling enough seats that they really don't need much of an offer.
As mentioned above, the city pairs are very interesting and with the large number of destinations from certain western cities, it appears that is where they want to drive additional sales/bookings.
As for Oneworld, I also received emails from AA and BA for their 125,000 Fall Bonus Promo and signed up for both. (Sept 22 2015 - Jan 31 2016).
I would hardly say no to 25,000 miles for J