Hello,
Part of the solution is requiring x:data forms for registration. Yes, as Matthias pointed out this will make life difficult for existing clients. So we need to define a transition strategy. Clearly define how the x:data-only registration works and set some goals for deprecating the old way of doing things.
don't think that clients are a problem. Once this is implemented in the first servers we will see it also in clients. At least this it what always happened in the past.
If we support media-in-forms (e.g. CAPTCHAs) we may have even stronger weapons. See XEP-0221 for the media element definition (recently moved from XEP-0158).
i agree, media-in-forms and CAPTCHAs is the way to go. And with that we are also prepared for new technologies. Because there exist decoders for the most CAPTCHAS today.
Alex
