Hi, Ben @ MySpace here,
Yes, At the moment Apps are unable to be added to what we call "special profiles", such as bands/artists. We know it's a bit of a bummer right now, but it is something we're working on and will have a deployment for shortly. However I can't give any dates as it's part of a stack of work we need to complete that's being prioritized.
As for being able to reference tracks, it's not something I beleive we've looked at. There are some limitations on what we can do in this area for rights and permissions reasons (an artist may or may not want their music - or info about it, such as number of plays - accessed by 3rd party apps, etc).
If you have some examples of what you are trying to do (email me directly if you prefer, bmetcalfe [at] myspace.com) it would help me build up a usecase for this!
Thanks!