The only reason I would be interested in a .CO is for resale, and the vast majority of premium keywords were off the market months before open registration began.
Developing a .CO will just lead to consumer confusion, and traffic bleed IMO.
I would develop a more recognized, credible gTLD like .NET/.ORG, or respected ccTLD far before any .CO
For resale I would rather have a domain like Music.co, for development I would prefer a domain like RocketMusic.com, as the cost is much lower and .COM is the global recognized brand.
Brad