Lieven some make it and some dont is purely down to what P.R. and airplay they get.
Record companies mostly dictate who is and who isnt cool. Same as the image etc, it is not the band so much as it is their gurus telling them what to wear, what to say when to say it, where to say it.
But with more use of the internet abnds if lucky enough can make it on their own.
A few that I know of that have used the internet in a big way to get started are Sandi Thom, she started doing live gigs from her house and broadcasting it live on the web, she got such a huge amount of hits that record companies started taking notice of her, then bought her over,lol.
Arctic monkeys released all their material for people to share before their very successful debut album was released.
David Bowie I think it was, was the first person to release a song on the internet, couldnt get it anywhere else meaning the record company had less of a say.
Radiohead decided to release an album recently on the web and let folk decide how much they wanted to pay for it. tom York the singer, paid 1 pence for it.
there will be a lot more but not enough. But if you get too much and the record companies get left out then i think it would be harder to find really good bands that will pull in thousands of fans for a gig in one area.