Recent revelations about the trilinear filtering techniques ATI has used in its more recent graphics chips, including the X800 series, have been something of a shock. The reason it came as a shock isn't because we've now learned that ATI is using an adaptive algorithm to reduce its graphics workload. Such algorithms make sense, done properly, so they don't harm image quality. Indeed, the essence of graphics is creating an illusion as effectively as possible, and shortcuts are big part of that enterprise.

The shock comes because ATI has consistently touted its own texture filtering techniques as superior to the competition's, talking down the so-called "brilinear" filtering algorithim used by NVIDIA and encouraging use of tools for IQ analysis that don't show the effects of ATI's method.

Well, currently there is an investigation going on by Toms Hardware and B3D, and so far they are having a problem finding any difference between regular Trilinear and "Trylinear" (as Hanners from EliteBastards.com coined it).

There's a blind test in which more than 50% can not see any difference or choose the correct trilinear.

So just how terrible this is remains to be seen.
BTW: ATI has been using this algorithm on the 9600 series from Cat 3.4 and noone has complained about that yet.....