basically it means "supposedly amazing."
so globalize it. your friends will think you're so cool.
"yeah, that movie is tart-zing."
"yeah, she's tart-zing, but i heard she's not that cool really."
something/someone who has the reputation of being outrageously cool/entertaining, but may or may not be in reality.
"oh my gosh, yeah, that movie is tart-zing, want to see it friday?"
"yeah, she's tart-zing, but i hear she's not really all that cool."