So teenagers wearing WWJD bracelets are idolatrous heretics? I am sure most of them believe it is simply a mnemonic to remind them to act humanely toward other people. However, if you wish to judge them and call them names, I cannot stop you.
I am saddened, however, since that kind of obsession with legalism can turn young people off the Christian faith. The basis of Christianity is a personal relationship with Jesus Christ. If teenagers use a mnemonic to remind them of the behavioral standards of that relationahip, I have no problem with it. Nor do I believe that Jesus, in His infinite love and mercy, has a problem with it either.
Yup, that's the practice that Moses asserted that God prohibited when he handed down the Ten Commandments.
I have absolutely no doubt there are people who are upset with arguments from the Ten Commandments. They'd rather we just all get along together and forget about that stuff.