As JonF mentions above, K/Ar dating is about the only method Creationists are willing to discuss. I'm sure we've all participated in discussions where the Creationists take the position that radiometric dating is flawed, and they invariably use K/Ar dating as the example. Evolutionists explain why initial Ar concentration isn't a problem and couldn't possibly cause millions of percent of error anyway, and then go on to mention the isochron and other methods that don't even have any initial daughter concentration problem. The Creationists rebut with more about K/Ar dating. The evolutionists explain again, and suggest again that the Creationists address how isochron and the other methods could all be wrong, and by identical amounts. The Creationists again rebut with more about K/Ar dating, and the cycle repeats. It would be a pleasant development to see Creationists actually address the other approaches.
Even without bringing in the other methods and focusing solely on K/Ar dating, the case against radiometric dating is incredibly weak, and can only be maintained by YECs who still don't really grasp its principles. I have a feeling that its popularity on discussion boards is because organizations like ICR, CRS, AIG, etc, have spent a lot of ink addressing K/Ar dating, so there's lots of source material.
--Percy
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