Apple release Garageband, a cheap, beginner-oriented music/audio sequencer, to become part of its iLife package. The page is somewhat light on specs, though if it uses AudioUnits for effects and instruments (as opposed to some locked-in proprietary format designed t subtract value), it may be usable as an OSX substitute for Cubase VST (which is mostly a platform for plugging softsynths into); it'd certainly be an order of magnitude or two cheaper than Cubase SX.