Hey Harold;
I think professional certifications struggle mostly in pseudo-professions like our own (I think I'd still prefer a certified doctor for my heart operation than the guy up the street)
The wide range of people working successfully in "learning and performance" without accreditation make it an unnecessary step to take for most.

The main purpose of a certification is to protect buyers from hacks and sub-par expertise. I think that the lack of value put on professional certification in training and development is partly due to to the lack of value attributed training and development itself. If it saved organizations the way doctors saved lives it might be a different story.

That said, I think as training/learning continues to professionalize in small steps around an generally accepted body of knowledge and the perceived value of learning continues to grow by organizational leaders the value of a "certification" will grow with it. If only we could get that "body of knowledge" to keep pace.

Tom