It seems to me that currently we use a large number of tricks other than ray tracing to get such things done as specular highlights, reflections, and refraction. This is all well and good for rather limited objects.
The bigger problems come in when you're talking about something expansive, that doesn't look good when it's approximated as a point object (for example, water).
It seems to me the real-time raytracing would be the only way to accurately simulate water, where you want to render how the light from all sources is reflected/refracted on the water, and how it collects on objects near the water (to get that shimmering effect near a swimming pool, for instance). It may also be necessary for realistic light attenuation within water (which is exponential, with the attenuation of each source of light, and how it lights underwater objects, based on distance light travels through the water).
