Frankly speaking, however, the graphics industry has gotten very good at extracting a lot of performance from the current vertex/pixel shader architectures, so the competition for anything new architecturally is a highly evolved and efficient architecture. The first rule of any new GPU is to be better at the previous API. Any trade-off which might move you away from that goal has to be evaluated carefully. If you look at some of the existing GPU architectures you can see some pretty big differences in terms of architectural efficiencies, and that is with architectures that, at least at the highest level, would present themselves as "non-unified" architectures. Even within that environment, you can see huge (almost 2x) differences in terms of performance delivered per unit of area or power.
If you assume that the competitors will be bound by the same laws of physics and economics, that alone would put one competitor in a dramatically better position. Would consumers be willing, for example, to pay twice as much for a graphics card that delivered the same performance as another, just because a particular graphics card was unified, or to pay the same price, but run at ½ the performance just because it offered some new architectural block diagram? I doubt it.
