This idea is sort of true while at the same time false.
Dedicated gaming consoles are merging with media/web devices in the long run. This is why MS entered the home console market and this is why the rumor of the neXtBox not having an optical media drive may have some weight.
Some of you already know my argument on PSV and smartphones, well its the same idea here.
In portables, the market is moving towards the smartphone and tablet simply being the one device type to rule it all. In a year's time their hardware capabilities will enable them to be equal or greater than anything in the dedicated gaming market, except built in controls. However, any of these devices can easily be paired with bluetooth controllers. This is the exact reason MS never made a dedicated portable console, MS fully intends Windows8 phones and tablets to be that device.
In home consoles, MS is forcing the market to be a fully integrated Web centric, media/gaming device. Apple and Google are doing the same thing with their respective TV based products. From iTV to GoogleTV to the rumored Apple actual television sets, by next year all will have high end gaming products from 3rd parties as well as standardized bluetooth enabled controls.
The only difference in all of these scenarios is first party content. MS, Sony, and Nintendo will still have their respective edges in this category, however 3rd party content will be essentially equal across all platforms, including Apple and Google's. (Apple already has strong and steadily growing 3rd party support and Google had a presentation last week stating they will have a unified large gaming division in 2013)
As for the big players; Apple, MS, and Google all stand to win big with this as this type of environment IS their bread and butter. Nintendo will largely be unaffected solely due to their amazingly recognized and desired first party products. They will move to continue to expand their media capabilities along with gaming, but they will remain the only fully gaming centric provider and will do well.
Sony on the other hand has the hardest route. They are not a PC/OS maker, they are a general electronics producer. They will continue their Android linkage and continue to keep the Playstation environment separate from general Android offerings, but PSN won't survive as Sony will be forced to continue to offer its massive nonGaming IP library to the general Apple/MS/Android stores. They can't leverage it in their market only and on top of that, unlike Nintendo, their gaming IPs, while many are very good, are simply not in the same league as Mario, Zelda, Kart, etc. They cannot hold up their hardware solely on their software when everything else is available everywhere else. Sony's best bet, to me, is that they make the PS4 as a GoogleTV device (to gain all it has and will continue to offer) with an obvious Playstation unique modification for gaming.
So back to the OP. It is right in that general media devices like the iPad will be the future of this market, but it is wrong in that it will be the "iPad" itself. Personally, I will own the Nintendo devices and likely a GoogleTV device. The latter will heavily depend on what actually emerges with Windows8. As I will continue to own Windows PCs and if the integrations is simply too superior, I may go that route and potentially even forgo Android as a platform I use. But that would require Windows8 being integrated with Google's services in some for as well. (i.e. Chrome, gmail, G+, etc)