Since this is bound to come up, I thought I'd state my official policy on music sharing for the forum. Soundtracks tend to be more of a niche interest with people, game soundtracks even more so, to the point where I don't think rigid copyright rules really apply for discussing this.
If you want to share songs or soundtracks with other people, I have no problem with you linking to Youtube or some other giant streaming service where the song is available. At that point, the giant corporation running the site is more liable than anyone here I think.
For linking to actual files, I'd say if it's a soundtrack that's easily obtained and is for sale, it's probably not a good idea to link to it since that's more clearly piracy against the company that put it out. If a soundtrack was published for sale at one point, but is exceedingly rare or difficult to find or obtain, I'm more open-minded about linking to it.
For soundtracks that were published, but are literally impossible to find a legitimate copy of now, released one time for free online by the publisher, but later taken offline, or never had an official score released at all (and are ripped from the game or obtained through other means), I feel it is your DUTY to share music of that sort that you think others might appreciate. When music reaches that phase, it can become endangered of being lost to oblivion. I hate seeing that happen to good music. I feel that rare soundtracks should be treated the same way as abandonware is when talking about old games. Purposefully using copyright law to allow good music to die I think should be considered a minor crime, even if it's not.