Making games photorealistic is merely an exercise in artistic skill. Raytracing any given existing game would only show up flaws in design and give an overall worse visual experience. Raytracing Quake, for instance, would leave a lot of areas poorly lit, or overlit. You need to really think about lighting, materials and colour perception to make it work without it looking bad.
You'd need top-notch artists being able to play with at least 1GB of working area for textures and vertex data to pull off a really good looking raytraced game, if photorealism was the aim.
Raytracing simpler, more stylised graphics could lead to some interesting visuals, but the market for such things is so tiny that it's not going to drive GPU hardware in that direction for some time.
If raytracing goes realtime, it will likely be as a side-effect of more efficient GPU design rather than an end result of that design process.
You'd need top-notch artists being able to play with at least 1GB of working area for textures and vertex data to pull off a really good looking raytraced game, if photorealism was the aim.
Raytracing simpler, more stylised graphics could lead to some interesting visuals, but the market for such things is so tiny that it's not going to drive GPU hardware in that direction for some time.
If raytracing goes realtime, it will likely be as a side-effect of more efficient GPU design rather than an end result of that design process.