$QQvarname is part of the set_form_variables set of functions. QQ denotes that the single quotes are turned into double-single quotes and the string is trimmed. This way you can throw it into the db with fairly small amounts of effort. It's used in practically every module.
BTW: I've been using a modified version of this function internally for quite a while that does the $varname, $QQvarname, and also $DBvarname. $DBvarname does returns:
'quoted value with escaped single quotes'
or
NULL (if it's empty)
Helps my efforts in being lazy.
If anybody wants it, I'll throw it into the distribution.
