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It can - also look into the app MuseScore (open source cross platform Finale/Sibelius type of application)
 
I didn't think MuseScore was offering a stable Mac port yet...could be wrong though. :confused:

If you are really serious it's hard to beat either the full Finale (I use Finale 2009) or Sibelius 5.
 
MuseScore - is finally a very stable and good release - it wouldn't hurt to give it a try before spending the cash for Finale or Sibelius - I personally own a copy of Finale 2007 which still runs great on Snow Leopard
 
Yes you can print sheet music in GB. It's limited with editing but it can be done. I would try GB first and to the extent that doesn't suit you then start looking into alternatives.
 
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