This may be overly convoluted, and will probably see a revision in the near-ish future but it works for now.
I create the playlist in iTunes on my Powermac
Run the audio out into my mixer that also has my mic running into it
Run that into my Win2K box for Real Producer
and hence to the internet and the edges of the known universe
It worked beautifully for my demo and I suspect it will do the same for live.
Will also be using XChat Aqua for chat purposes on my Powerbook as it has the feature set I like for UNIX/OSX chat.