Have only read the original thread posting.
It's nice to experiment with your own compositions. I have piano music on everything from US Cable TV to a Swiss Art Gallery. People just heard my work on MP3 Sites and liked it. Have also sold through i-Tunes etc. But when I was working Pro. many years ago (7 nights a week then), I just played what was required to be successful - the Copyright music of others (what they term as Covers nowadays). It's no use burying your head in the sand and not giving people what they want.
Performing on Internet:
Of course for anyone composing/performing own music there are no Copyright restrictions and you can do Soundclick, Reverbnation, Garage Band, MySpace etc. to your heart's content. The only site I'll ever do "Covers" is YouTube video. They seem to have a liberal attitude to this and it's a case of safety in numbers.
For anywhere else it's worth remembering that Copyright Music starts (at present) around 1919, so even those 1930 jazz standards are in theory still under Copyright. Anything before is usually Public Domain, hence many Classical performers can record and sell freely without paying to Harry Fox, ASCAP etc.
Performing Live to make money:
To work, and make money, most musicians just play what is required. If a premises has a music licence then you have no worries. You can always slip in your own stuff however, and test reaction.
