To resort to plain language instead of overworked metaphor, the problem with CAPTCHAs is that they're increasingly easier for computers to solve than they are for humans. This is perverse, because the whole reason they were introduced was that they were _hard_ for computers but _easy_ for humans. The latter part was a key design goal, and we are increasingly ditching it in favour of "just using a CAPTCHA" because they're what we think works.
So the point that seems reasonable to make is that people deploy CAPTCHA in environments where it is insufficient to the task. True enough. At the point where an arms race has developed over such technology, or other circumvention technologies (such as hiring cheap labor) is being used, it seems to me that in such an environment, the technology is fundamentally not suited to the task. It seems fair to say that CAPTCHA is rapidly evolving to the level of hook-and-eye latch protection, suitable for rudimentary protection on low-value assets, keeping the rabbit in its cage, etc. So, then, "replace it with what, exactly?" What if we all wake up one morning to find that our computers have gained an IQ of 6000? Will the computers be making jokes about "as dumb as a human" and debating ways to identify if they're talking with another computer or just a human? :-) ... JG -- Joe Greco - sol.net Network Services - Milwaukee, WI - http://www.sol.net "We call it the 'one bite at the apple' rule. Give me one chance [and] then I won't contact you again." - Direct Marketing Ass'n position on e-mail spam(CNN) With 24 million small businesses in the US alone, that's way too many apples.