Hmmm...you're a BMW owner who's not aware of failing ABS systems? I guess you're are equally unaware of failing drive shafts and final drives either. But then again, your user name is wondering, so I guess you like to wonder about things, but why wonder, when a simple search will yield all types of ABS issues, including failures like this $3000.00 BMW failure:
http://forums.bmwmoa.org/showthread.php?21924-02-K1200LT-abs-brake-failure-warning-light
ABS will and does break down; when it does, it's very expenisve to fix. ABS can cause other servicing headaches as well, i.e. there are certain bikes whose shocks can't be removed, without having to move, as in remove, the abs pump, and then having to deal with all the concomitant problems of bleeding the ABS plumbing as another example.
Oh, and by the way, the stopping on a wet pad BS video displayed above, is ridiculous. Who TF does not slow down in the wet? Give me side by side comparisons of an ABS equipped bike stopping in the wet at 30 mph, and a non abs bike stopping at slower speeds, say 25 or 20 mph, considering most riders will slow down in the wet, and get back to me about the results. That type of nonsense, i.e. comparing braking distances in unrealistic situations, only undermines the credibility of ABS proponents. Real riders will slow down in the wet. Or, OTOH, if the *real* message about abs and other rider aids is that you can ride without caution, beating all others to the coffee shop, as their real benefit, then yes, I agree, abs will help careless riders taking higher risks to better perform on real world roads. But, tell that to the police office who asks why you were not riding according to road conditions when you try and explian to him how safe your bike was supposed to be, after you crash in the rain doing the speed limit instead of using discretion and riding according to the road conditions.
I'm not an ABS hater, I just don't want it on my bike.