The Beatles may well have influenced many, many bands, and perhaps myself indirectly by influencing those who have influenced me, but as for direct influence - I've listed to perhaps two of their songs ever and disliked them both. Their playing was in no way even special to me.
What exactly did the Beatles change? What barriers did they break?
There is very little barrier-breaking done by anyone nowadays... Classical composers have written massive books on harmony and melody that cover almost everything that is now seen as "new". Take using a Bb Major chord in C Major, for example. Using the b7 major chord in a major key was popularized in some songs around the 60s-70s, but it's also found in some classical compositions.
Another example. Pearl Jam claims Hendrix as an influence, and Yellow Ledbetter shows this with the hammer-on/pull-off chord playing, such as...
|---------------------------
|---------------------------
|---------7---7h9p7--7------
|---7-----7---7------7h9----
|---7h9---------------------
|0--------------------------
But these suspensions and resolutions were all studied and many applied in classical composition. I'm currently thinking of one piano piece I know that plays an A Major chord with the third on top, to the fourth, to the second, and back to the third.
Brazilian and Latin folk songs use exotic chords such as +7, m11, and 7#9, but the 7#9 chord is seen as "The Hendrix Chord"... why is credit given to the wrong people? The majority of people listen to Rock and Pop music rather than other genres, so if it's the first time they've ever heard it done in a Pop setting, they assume it's the first time it's ever been done. *sigh*
"You must stab him in the heart with the Bone Saber of Zumacalis... well, you could stab him in the head or the lungs, too... and the saber, it probably doesn't have to be bone, just anything sharp lying around the house... you could poke him with a pillow and kill him."
- Aqua Teen Hunger Force, The Universal Re-Monster