first released by other artists
I wondered just how many other Lennon-McCartney penned numbers were not done by The Beatles. With Wikipedia to the rescue, I found there were a fair number, some had a Beatles version released later, but all these below were done by other artists first. It was a case, similar to Motown, where the Label's writing talents were encouraged to give songs to other artists who needed material, and it was a boost to the artist as well, simply because it was known as written by John and Paul. Wikipedia entry here.
Many of these charted well and I remember hearing most them on the radio at the time. Two principal exceptions are TQ, and The Strangers, who I had never heard, nor heard of, until doing this. Most have not strayed far from The Beatles' sound, some sound as if trying to copy them.
I have favoured live footage of the time for its period flavour, even if the sound is dubbed from the single. Check out the audience and the girls dancing in the Peter and Gordon "Nobody I Know" clip. See American P. J. Proby the big poser, channeling Elvis and working the girls in the studio audience. I also spotted in the "Love of the Loved" clip at 0:51 this fantastic photo of Cilla Black, Petula Clark and Sandie Shaw together. ...be still, my beating Heart! (William Mountfort, 1705)
POSTSCRIPT 28/08/15 I found out the venue and more pix of the girls, now shown at the page linked above.