Gary RV Roamer said:
One of the major differences between a world-class musician and a competent one is the "extra" sound they impart while playing the same notes. The subtle difference in technique that makes you hear/feel the emotion in the sound.
What constitutes "music" will always be argued by musicians and non-musicians. There is a quote about jazz, credit is usually given to the great Miles Davis as the originator, that it is all about "the notes you don't play."
Musicians are varied in their soloing. Some improvise, some don't. Pickers like Jimi Hendrix and Jerry Garcia NEVER played solos the same way twice. Sure, they might have a pattern to go by, especially one made familiar to their audience via a recording, but it was always used as a starting point, their solos soaring off into space from there. On the other hand you had someone like Louis Armstrong who practiced and practiced his solos and they would be the same every time, a matter of pride to Armstrong. To me, if I want to hear the song I can play it at home, if I want to see and hear the musician do what he/she does, I go see them live.
Personally, I hate to use the term "lead" guitar, you are either a guitarist or not, "lead" is an arcane term used more as an ego boost for musicians (many of whom are known for having fragile egos). I play in a blues band with another guitarist. Someone once asked me if I played lead guitar and I replied I played guitar. He asked if I was a "better" player than my bandmate. I replied that he did not understand music as it is NOT a competition.
To some of us, the magic of the music is to get lost in it, to get into that place where you don't think about what you're playing, your fingers are transmitting the notes in your soul without you thinking about each and every one of them. It is a truly magical place, probably as close to living in the "now" as one can get.