@John Brown:
I think you're right about lots of talented (not only) youngsters on youtube. And it also seems also to be true that as well as talent along with genuine real musical skill, anyone needs a large slice of luck/being in the right place at the right time to "make it" - whether as an orchestral player, an opera singer, or in a pop group (as random examples). I guess then that it's a natural idea to make a youtube channel to "get yourself out there" in the hope that you may get that important first break, and possibly, along the way, perhaps even earn a few bob from it (although I believe the pickings from that are generally pretty slim).
Anyway, these youtube efforts provide, at the very least, some genuine surprises and real entertainment for blokes like me who can't do anything musical at all really, except sing a bit. (And BTW, for me that includes the mouth organ, which as has been previously pointed out, is purely a matter of personal taste).
Thanks for the Mandolin link Jacob. Good. If you (all) want something really "outlandish" though, try googling "The Ukelele Orchestra of Great Britain". If you haven't already heard of them, they play everything from The Dambusters March to Life on Mars or Wuthering Heights. Quite "ridiculous" really one would think, but as the Torygraph described them - "plucking good entertainment". That's especially if you see them live (they tour a lot).
Long may all this stuff continue. At least it often helps me learn new songs for the choir.
AES