Well, the difference is noticeable! I don't think it's possible to say that it has no discernible effect
at all.
But I'd still say that the effect it has does not offset the cost of either financial value or performance impact. And I would still argue that it has no discernible effect on
gameplay. It's not the same type of innovation as:
- Dedicated, Physics Processing...allowing for games to accurately track the trajectory of bullet arcs or respond realistically to forces applied on flight surfaces. This tech revolutionized what could be done with simulations in games, and gave us things like ArmA, much better Flight Simulators, etc.
- Hardware Transform and Lighting...going from lighting being based on actual gamma settings for an overall frame to point-based or volumetric lighting. This allowed for real-time flashlight cones and spheres of light cast from torches, lamposts, etc. It revolutionized the way that environmental lighting could work and did wonders for especially the horror / thriller / stealth genres.
In comparison, Ray Tracing is "pretty"...but it doesn't
do much. It's mostly just a nicer paint job. It will be lovely to have when it becomes standard. For now, I'd imagine most people who spend the money on it will wind up feeling that it's not really worth the cost once the novelty wears off -- especially not when it winds up costing them 30+ FPS in certain situations...and games still look excellent using standard T&L.
Also...there will be the bugs...
But, I don't mean to sound totally negative on it. I think the actual effect is really cool!