dernier cri - dare-NYAIR CREE - the latest thing, up to date
Example: "The tradition of celebrating the entire Super Bowl day in Louisiana has become the dernier cri in various sports-minded cities in the upper Midwest."
As a starter: and as a former teacher in English, I hope to add to reader's vocabulary by presenting a word a day in simple terms that anyone can understand - from current use in publications, radio,TV, etc. Remember: use a new word three times in a day and it's yours forever!