There's going to be another round of consoles. There's another Xbox coming, another PlayStation. Anything could happen in the next couple of years before they're released. For instance, Apple could start selling "smart televisions".
There have been "Apple TV" rumours for years, even before there was the current bolt-on AppleTV. (Here's one of today's.) But now Apple's a bit of a gaming powerhouse—despite, at times, seemingly not giving much attention to gaming itself (e.g. the smelly old design of Game centre). And while the imagined Apple smart television likely wouldn't be much more than an LCD panel plus the guts of an AppleTV (which are the guts of the iPad, iPod touch, and iPhone, more or less), it's entirely possible that a whiz-bang interface—the one that Steve Jobs reportedly "cracked" before he passed away—would draw in a bunch of new users.
New users that might not have a need for a console anymore. Users who can get their casual game fix from iOS games they download from iTunes App Store, sitting on their couch. Users who might use an iPhone or iPad as a controller.
"Traditional" gaming isn't going to die as long as there are still enough people around who want a dedicated gaming experience. (10 million+, let's say.) But as I was discussing with some readers at the Kotaku party at Blizzcon, I think it's very possible this next round of consoles could be the last, especially if Microsoft, Sony, and Nintendo don't fully embrace the capabilities we've always wanted from a do-all set top box. That won't mean just games, but movies and cable television, internet browsing, social interaction—the whole schmear. Heck, Gabe Newell thinks so, too. (Microsoft is heading this way in fits and spurts, but also has a sad history over the last decade of innovating in features but neglecting platforms and branding; still, Xbox is their strongest individual entertainment brand.)
If Apple does throw its hat fully into the living room, the traditional consoles are going to have an even more difficult time getting the penetration they need to achieve the economies of scale on hardware and software-to-hardware sell-through rates that make the console business profitable.
It's a bit of a surprise that the three console makers have stuck around this long—I don't see how the market will support four. Nintendo like to brag about being the games company that engineers paradigm shifts. An Apple Smart TV as a games content trojan horse could have the paradigm shift right out from their—and everybody else's—feet.