First off it depends on which market you are talking about because I believe that what Nintendo split asunder will not be put back together. I think for now on there will be a group of purely recreation and social gamers which will become more distinct from the total immersion gamers. I say this because there certainly will always be a group, mostly between 12-25 and mostly male who are looking for a highly competitive experience or an alternate reality experience that is the most realistic simulation that technology will support. As the technology advances, these types of games will become less and less accessible to gamers not wanting that intense an experience.
The other group will be looking for greater simplicity of control; intuitive and a short enough learning curve to allow guests at a party to get involved in game play. To achieve this they will sacrifice precision of the type needed for seriously competitive gaming. They will be looking for games that will allow them to play for an hour or less at a time and deliver a satisfying experience. They will also be looking for games that are playable by different age groups and skill levels with some mechanism to even the playing field so that the more skilled are challenged but the least skilled won’t be frustrated. This is the genius In Mario Karts behind the IA controlled weapon strikes that disproportionally strike the player in the lead. This sometimes frustrates and even infuriates the better gamers, but it does mean that the most skilled driver won’t always win. Mom or the 8 year old will win just often enough to enjoy playing. In Super Smash Brothers (all versions), the controls are designed so that simple button mashing will let you do well enough to feel involved and just once in a great while win over a much more skilled player.
These goals are too incompatible to probably ever be integrated into a single console again. Anyone wanting both, say a serious gamer who still wants to be able to play socially with non-gamers will just get two consoles. Many already have. The cost of the consoles ought to come down like other electronics to where this is an attractive alternative.
I think the winning consoles will disrupt the market place by sacrificing the ability to appeal to both groups for optimization to appeal to one group. The one can be bleeding edge, relatively expensive and offering immense precision and immersion at the cost of accessibility. The other will be less expensive, lower tech and designed to offer the greatest fun for the most people without wasting resources catering to the more intense gamers. This will create great opportunity for two manufacturers although it is harder to see where there will be room for a third. If the third company tries to disrupt by appealing to both groups (ala PS2) I think they will lose because each of the two groups will prefer the machine designed for them rather than one compromised for both.
If I had to guess, Nintendo will go for the recreational/social gamer and MS will go gung ho for the virtual reality intensity crowd. Sony looking back to happier times may be tempted to try to recreate the universal machine like they did so successfully once before. But I think it is a different time and the technical divide won’t make that possible.