Why is Kuler based on the historic color circle, rather than the digital color circle? If the specs for the colors are designed for digital production, doesn't it make more sense to use a more compatible description of color schemes and harmonies? If the majority of your clients are involved with digital production, why not update the color theory aspects of Kuler, as well?
In digital color theory, the subtractive primaries are CMY. The complement for C = Red; for M = Green; for Y = Blue. This also impacts most of the other color harmonies (triadic, split complementary, tetradic). In my intro Digital Color Theory class, it can confuse my students when the information in Illustrator and Kuler contradict the information that is current for digital systems. Is there a chance that this issue will be addressed in Kuler in the future?
An excellent question, but one that has come up repeatedly over the last seven years, so I don't like your chances of getting a satisfactory answer from Adobe!
Unfortunately, even the digital colour circle (that is, Hue angle in HSB) is not a great solution, because it is very uneven perceptually. In addition, though this doesn't seem to be widely appreciated, opposite hue angles are not true additive complementaries except on the Red-Cyan, Green-Magenta and Blue-Yellow axes:
Better solutions might be to offer a hue spacing consistent with Lab space (perceptual) or CIEL*u*v* (near perceptually even, but with straight-line additive mixing).