In my opinion this will teach anyone the necessary skills to be able to play the guitar, it starts off slowly and teaches you a few notes and gives you a chance to get a feel for the rhythm and tune. Once you pick it up it makes it a little harder by adding some more notes until eventually you are playing the entire song. This could take minutes, hours or days but given the time and practice you will do it.
Most of the featured tracks are fairly easy going, there's no Dragonforce, Slayer or Metallica. A shame maybe but I'm sure the majority of players won't be looking to become a shredder, but don't worry I'm sure they'd add these into the DLC if there's a market.
I've played guitar for 16 years and if I'm honest I struggled initially, it's a bit strange at first because it's a different way of learning to how I am used to but once you get into the mindset it becomes incredibly simple.
Pro guitarists are endorsing this and I really hope it takes off, it's not your standard rhythm game and it doesn't give you the party atmosphere but it will teach you the fundamentals of playing a real musical instrument. This is serious entertainment and not just your pick up and play plastic kids toy guitars.