http://www.mmaglobal.com/bestpractices.pdf

Highlighted in the guidelines are updates to general conduct (section 2), advertising and promotion (section 3), marketing to children (section 4) and explicit honoring of SMS STOP commands (section 8). We’re happy to see MMA continue to push forward with policies demanding that participants in the mobile ecosystem honor consumer’s choice and participation. We actively review our logs and add additional opt-out phrases that we see commonly used, such as sentences starting with “please remove”, or “take me off”, for which we honor just like any of the other required opt-out commands (STOP, STOP ALL, CANCEL, QUIT, END, UNSUBSCRIBE).