IMO the problem with consoles is multi-fold.
First you have the interface. The xbox 360 and ps3 interfaces are horrible. Apple has a very simple interface on the latest apple tv iOS, you just add apps to the main screen.
The second problem is boot up time. It takes nearly 5 minutes to boot my xbox 360 or ps3 and get into a game. I don't have the time or patience to deal with this sort of thing anything. I don't devote days to gaming anymore. I have a few minutes to play and then the kids or the wife wants to watch something on the tv and i'm screwed until they goto bed. Well i was screwed before i got my iPad
The 3rd problem is price. I don't want to pay $59.99 for games and have a physical dvd or bluray disc laying around. The pets and children do not understand how delicate they are. I'd much rather buy a game for $.99 - $4.99 then buy one for $59.99 and not like it. I can afford to buy 12-30 games and not like them all, and that's highly unlikely to happen.
In fairness the current consoles are over 7 years old, and the hardware is probably more like 10 years old. They have held out pretty damn well.
Lets wait and see what this years consoles are like. For all we know they will be instant boot and use a nicer UI than the ATV.