More interesting points being made all around. I'm not sure if I would say there is a 'certification war' akin to VHS/Beta going on - I think both are suited for different purposes. The IIBA has a fairly strict requirement around number of verifiable and direct hours of experience that you must have prior to gaining certification. To my knowledge the other certification does not have this requirement.
Precluding that the IIBA certification is a way to get junior or wannabe BA's to give up money (since they don't qualify), one could look at their existence this way - such a certification exists to weed out so-called BA's with the term plastered across their resume and all the right terms listed in their previous experiences/skills. Granted, a good interviewer will expose these people, but sometimes PMs or directors who are not that knowledgeable in Business Analysis can be fooled relatively easily. A certification process can be used to ensure that people have a standard set of knowledge as well as direct experience in applying that knowledge.
Again, I'm not all for such certifications - in fact I am looking to get into Project Management in the next year or two and think that the stringent PMP requirements may inhibit my options locally due to the many 'PMP preferred/required' jobs I see. But I can see their value as a starting point for evaluation for a candidate, not necessarily as a hurdle nor a final decision making point.