Back in April Jørn Lomax was awarded a Google Summer of Code (GSOC) place to work on the (as it was) Fedora Audio Spin. While there have long been people working on music and audio in Fedora, a GSOC place means there is someone with time (and deadlines) to focus on getting things done.
The project is now burning along in 16/16 time as Fedora Jam.
For the uninitiated a 'spin' is a customized Linux distribution aimed at a particular goal without including the kitchen sink (you can always download a sink later if you want). They can often be run live (without installing) as well as installed to give you a system optimised for, in this case, making music.
As well as making sure all the programs you might need are there a spin can also be crafted so it's easy to set up and things you need, like real time audio, work as well as possible.
What will be in it? This is still being worked out, but you can expect digital audio workstations like Ardour, scoring and music writing tools like Lilypond, lots of audio plugins, and instrument and synth tools like Hydrogen and Guitarix (the guitar angle). With some quiet orchestration to make sure it all works in harmony.