I'm not a lawyer, but in some places, isn't it hard or next to impossible to get your work into the public domain?
I'm also not a lawyer, but I've asked this question of some law professors, and the consensus appears to be that at least in common law states, while there is usually no de jure mechanism for placing work into the public domain, if such a case ever went to trial you can be 99% certain that the judge would wave a magic common law wand to fix that.
That said, wikipedia's "I place this in the public domain, or if that isn't possible, I grant anyone the right to use this work for any purpose, without any conditions" is probably the safest approach.
I'm also not a lawyer, but I've asked this question of some law professors, and the consensus appears to be that at least in common law states, while there is usually no de jure mechanism for placing work into the public domain, if such a case ever went to trial you can be 99% certain that the judge would wave a magic common law wand to fix that.
That said, wikipedia's "I place this in the public domain, or if that isn't possible, I grant anyone the right to use this work for any purpose, without any conditions" is probably the safest approach.