This is because its Microsoft right? and Microsoft is incapable cross-platform software right?

So its just co-incidence that it also runs in OS X right?

I wish there was a filter to remove these baseless un-informed comments.

Microsoft itself supports silverlight on OSX (with safari/FF), so it will guaranteed to run there.

Any other platform/browser variant will probably need to be supported by moonlight to run (http://mono-project.com/Moonlight).

Moonlight compatibility is actually pretty advanced, as far as I understand there is a support contract between MS and Novell (Mono) that gives Novell access to all their Silverlight test suites, which is actually a big step in true-compatibility as if all the tests pass there is a very good chance that your silverlight app will work under linux as well.

Although even if Silverlight works it wont be able provide the User Experience that Spotify does, which is a very well-written truly native application with a primary focus on speed.

Well everyone at work uses it, so the best way I use it to discover music is to actually listen to each other's playlists.
To share a playlist just right-click on the playlist click 'Copy HTTP Link' and IM the link to a friend.

Other than that I just basically search for genre, i.e. 'acoustic', order by popularity and let it play.

They also have Artist radio (which I don't use very much), which basically looks like listening to a random set of tracks from similar artists.

I've actually discovered a lot more music I like on Spotify than any other service for a long time.

It's actually that good a service that I'm probably one of the few people paying the monthly £9.99 p/m to listen to music without interruption, as I think the service is actually worth paying for.

Because it's the fastest music player with the smallest footprint available that lets you listen to *any song* you want.
You can search and play a song in milliseconds.

There is no equal, period.

+ ReSharper.

Maybe your ok with "Qt apps look and operate just fine on Mac and Windows", but Google wants to build "the best browser they possibly could" for the most popular platform available, end of story. They've ended up producing the fastest browser available with a simple, clean and unobtrusive UI.

Yeah thats the main reason, not the fact that they are making billions a year with their current business model to giving most of their services away for free so they can get people hooked on their stuff.