I find most analysis of the video game market rather shallow, and it seems most people fail to consider that people can own multiple devices that play video games; and play games on each of these devices.
(Roughly) 40% of people who play games on a console (Wii, DS, PS3, PSP, or XBox 360), tablet, or PC play games on 2 or more types of these devices; this is up from (roughly) 30% in 2009. I could be wrong but I suspect that by 2016 60% of people who play videogames will play on multiple kinds of devices.
In my opinion, what tablets and smartphones have done is really brought to the forefront people who were playing flash and simple puzzle games; and it has not really impacted the "bread and butter" of any existing platforms. The handheld gaming system has probably seen the greatest impact being that the GBA and Nintendo DS were full of these kinds of games, but I still notice these games being made for the system; and they're now moving to being digitally distributed at low cost (often in a cross platform fashion with the tablets and smartphones).
