CIELAB was developed as a color space to be used for the specification of color differences on reflective media. It was not exactly perceptually uniform and this non-uniformity was addressed in subsequent colour difference formula.
I dont think it was designed with image editing in mind. Hence the problem.
CIELAB is however used in the ICC profile format as one of the Profile connection Spaces.
CIECAM02 is a more perceptually uniform colour space and is used for gamut mapping. It is quite complicated to use requiring several input and and output parameters. I have been using it in a RAW image pipeline with reasonable results. My approach is to use a camera sensor RGB to XYZ matrix (optimised by error reduction in CIECAM02 space) to achive accurate scene referred colorimerty before passing to CIECAM02.
I have not however used it as an editing space although it wouldnt be to hard to implement or design an interface for such. Cliff Rames has produced a good CIECAM02 plug in for photoshop as mentioned earlier in this thread.
This can also now be done using ACR (see Creating scene-referred images using Photoshop CS3
and ) and then passing to the CIECAM02 plugin. The scene viewing conditions would then need to be entered.
CIECAM02 has several colour spaces for example:
JMh Lighness Colourfulness and Hue
JCh Lighness Chroma and Hue
QMh Brightness Colourfulness and Hue
QCh Brightness Chroma and Hue
Jab Lightness redness greenness and blueness yellowness
also has correlates for saturation
CIECAM02 is used as gamut mapping space and might yet be a ICC PCS.