Until today Spotify was just a music-streaming service, albeit a very good one.
But this morning's announcement of an enhanced player (Spotify calls it "an evolution") should really start to take the fight to iTunes.
So here's some stuff you need to know before downloading the app.
1. It will import from iTunes
You can add tracks from anywhere on your computer and, crucially, this means your music library and playlists from iTunes. Then you can browse the combined library. But it's just a catalogue of what's already there (rather than actually importing the files as such) and uses Gracenote to iron all the name-wrinkles out.
2. But there's something missing
While you can sync playlists and your local music to your Spotify mobile app (and wirelessly too), you won't be able to sync your music directly with the iTunes apps on an iPod or iPhone. So you'll still need iTunes, kids – well until iPhone 4.0 enables multitasking at least.
3. There's a people column
You can connect up Facebook to share playlists and tracks with friends as well as Tweet what you're listening to (although you could Tweet track links previously). Music your friends have posted on Facebook will be visible in the Feed section. All of this builds up your Music Profile.
4. Your Music what?
There's a Spotify Music Profile. It acts like a control centre for your sharing, and enables you to build your profile using your friends. You can also post a link to your Spotify Music Profile anywhere on the web or post it to your Facebook page, blog or site. Your weekly top six tracks and artists can also be published. So where does this leave Last.fm?
5. It auto-shares playlists
Connecting up your friends means all your Spotify and imported iTunes playlists are automatically shared. Although you can turn them off, it's something to bear in mind, especially if you have playlists you wouldn't want everybody to see by default.
6. You can star your tracks
Every track or album on Spotify can now be starred, so you can tag and sort your favourites into a special sub-folder.
7. Add Spotify users
You can add other Spotify users to your Music Profile by simply searching for them by username. For example, searching under 'spotify:user:username' will bring up their profile (if it's published, of course).
8. Send tracks to friends
As well as the social sharing bits, you can also drag and drop a track or album over a friend's name and it will appear in their Inbox.
9. See how popular you are
Playlists you've posted will display how many times they've been added by your friends. Clicking on the number brings up the names of the people that have added them.
10. Your offline playlists can now be online
Providing your iTunes tracks match tracks within Spotify, your iTunes playlists can be shared online with friends. If it uses music which isn't in the Spotify catalogue, then you won't be able to play it.
11. It's a bit clunky
Time will tell, but it's still beta software (it's only gone from version 0.3 to 0.4) and the new features are a bit unintuitive - MP3 integration doesn't work as well as we'd like. Download it now and tell us what you think.
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