The New Yardbirds. An absolutely stellar, classic performance!
This new lineup didn't sound anything like the Yardbirds, though. The huge departure in the expected "white-boys-playing-blues" style left these early audiences dazed and confused. They didn't know what to make of it. You may notice the question-mark expressions on some of the audience's faces in the video. They were following it, they were liking it. But they didn't know what to compare it to.
This style was on a whole other level. Bonham's drums were like cannons. And songs had to be written accordingly, to accompany such a thunderous sound. And that's kind of the direction Page wanted to go, anyway. So he was pleased.
If any of you guitar players have wondered how Page got a twangy Fender Telecaster (typically used in country music) to growl like an animal, check out this demo of the fuzz box he was using in the video, and on the first album.
https://youtu.be/LUBUmO7grAg