John Mayer isn't just back on Katy Perry! He's back onstage!
Just a few months ago, John was battling some pretty serious throat issues, but Today is a brand new day! In fact, he's ready to take on The World!
Ch-ch-check out the video (above) to see Mr. Katy Perry perform his classic Waiting On The World To Change!
And see one more bonus performance of Queen Of California …AFTER THE JUMP!!!
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Tags: john mayer, katy perry, music minute, tv news