I upgraded from the Canon MP990 to the MG8220 a few weeks ago. I upgraded for the native AirPrint and Google CloudPrint features.
The print head in the MG8220 is the same as the MP990. Ink usage is about the same between the two units. The first three sets of ink replacements will happen faster than the future ones. I could explain why in a short essay, but basically it has to do with proper head maintenance. A good amount of ink is used in the initial setup of the machine to align the head and also fill the head and its small internal reservoir between the tanks and the actual head.
I printed six 4x6 photos and about 300 pages on plain paper before I had to replace any ink tanks from the inks that came with the MG8220.
I print almost every day and learned with my MP990 to just leave the machine on 24/7 unless I know I will not print for days as the MP990 and MG8220 prime the ink tanks every time the machines are powered on.
If you want to get the MG8220, get it ASAP as it is a discontinued unit and at this time Canon does not have an exact replacement successor unit. I do not think Canon will have a 2013 AIO model with film scanning, CCD scan sensor, etc. The top of the line model looks to be the MG6320 with the lower quality CIS scan sensor.
Usually new Canon printers are first posted on Canon UK’s website. The new MG6320 and MG5420 for example were posted there in early September, but were just announced on Canon USA a few weeks ago.
Compared to HP’s Photosmart machines that have 564 ink tanks, the ink usage is better on Canon’s CLI-226 machines by far. The same if you want to compare Canon’s ink usage to what the Epson Artisan units use too.
To sum it up; Canon is a better bang for the buck when looking @ OEM ink usage, machine features, quality of built and you get actual USA-based support and service.