Just downloaded the iTunes update (had to do that manually from the iTunes web page; Software Update didn't see it) and it's "gathering information" about my library now -- fun to see how this all works out =)

edit:

After about 25 minutes of crunching it ended up matching a bit over half my library of 5,677 songs, having to upload 2,507 ... as I'm pretty sure my library is on the small side, I wonder if this scales reasonably to a larger, more "normal" one =)

/edit

edit 2:

Now I think about it, since it uploaded my copy of, say, William Shatner's version of "Lucy in the Sky with Diamonds," does that mean someone having the same version in their library won't have to upload theirs? Or will there be zillions of separate versions of that seminal classic?

IOW, if song X is uploaded once, does iTunes Match use that to serve everyone else who owns it?

/edit2

I think that it uses yours to supply everyone else's

Thanks!

Interesting: I started with 5,677 songs in my library and now have 5,813 and counting up as it goes (taking a long time to upload stuff, I guess ;-) ... it appears to be adding 256 kbps versions of purchased songs to my library if the ones I had were at the old 128 kbps rate and flagging the old ones as duplicates. Since it's still grinding away, I don't know if it will eventually replace the 128 ones or just keep them flagged when all is said and done =)

iTunes uses songs that are contained in the official iTunes catalog. So if you have some song that iTunes doesn't offer, it doesn't "match" the song. So, it doesn't matter if you and I have some arbitrary bootleg song, or a song that isn't available via iTunes - we would both be uploading the song independent of each other.

Just signed up. See how this goes. I'll be replacing a lot of Amazon MP3s with AAC versions.

Tempting, but at $25 a year, I'm not sure if I want to pay that.

What happens if, after a year, you decide not to keep iTunes Match? Does it take away the stuff that you downloaded from iTunes Match? Or does it actually let you keep those files?

It does not remove those files from your system. It will remove all of your uploaded (unmatched) content from their servers and kill your ability to download future matched songs.

What I'm using it for is upgrading ~1500 songs. Moving from mp3 to AAC, and everything to 256kbps. It will also allow me to easily download songs to my work computer that I have at home and want to listen to.

I guess the one thing I like is to upgrade the ones that are lower than 256, but not sure how many I have.

Other than that, I load up my iPhone with the music I want to listen to, so I don't see any real advantage (for myself) of having the ability to download to iPad/iPhone

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Has any of you read the point that this iTunes music matach means Apple is encouraging Piracy? I have read several articles, but it doesn't make sense to me. Not including a link here. It is easy to find reading on the subject.