I had not realized that the Yardbirds had as guitarists Eric Clapton, Jimmy Page, and Jeff Beck. That has to be some sort of record for awesomeness in a band.
What's weird is that their music is fairly pedestrian, at least to my ears. Perhaps it was revolutionary when it was written in the 60s, but I was listening to a lot of music by the early 70s and it never really struck me as being particularly revolutionary. This is their biggest hit, and there's not much that would make you think "Guitar Band". It's said that Clapton left the band in disgust over this song because it was "too Pop".
Maybe it's because music like this didn't get a lot of radio time. The bit starting around 2:40 is 100% Jimmy Page.
This actually sounds like it might have been influential on The Doors.