We played it over and over and over tonight. On first listen, my wife heard Laurel and my two daughters and I heard Yanny, all of us thinking it was clear as a bell. After several times listening closely I started making out the deeper voice saying Laurel underneath the more tinny voice saying Yanny. Then Laurel took over and I haven't clearly heard Yanny since. How weird is that?
To try to get my daughters to hear Laurel, I held the phone we were listening on in my lap and leaned over it, muffling the sound. When it was muffled, both my daughters heard Laurel (they freaked out). Playing again unmuffled, one went back to Yanny and the other stayed with Laurel. My wife never did hear Yanny.
What a strange effect.