So, is anyone besides me using me? I've had Google Music since it was in beta, Amazon Cloud Player for the last few weeks, and Itunes Match for the last week or so, so I figured I'd post up my experiences with them, outside of buying music, as I haven't bought a new album in something like four months, and not at all from Google Music or Amazon MP3. Google Music Google Music, like all things Googly, is pretty simple. You register with your Google ID, install the uploader, and then upload your music. It doesn't matter if you delete music off your computer; it'll stay on the Google server. There is an official app for Android, and a web app for IoS, along with a couple of third-party apps (Gmusic and Gomusic are the ones I'm aware of) for IoS, and a desktop computer version. Google Music doesn't upconvert your music, or let you re-download what you've already uploaded, but the service is free and can store up to 20,000 songs, which seems to be about the norm. I uploaded my entire library of about 6,500 songs to this; it took about a day for it all to upload. You also occasionally get free music from Google with this based on what you've uploaded, which is a nice freebie. Amazon Cloud Player Amazon's Cloud Player is tied to the Amazon Cloud Drive program. It, like Google Music, allows about 20,000 songs to be accessed from a variety of devices. I can't speak to if there's an app for Android, but IoS support is awful to say the least-you can't so much as switch tabs in Mobile Safari without your music stopping, so it certainly didn't strike me as very useful for mobile music; the desktop player works fine, though. Playing in the background (achievable with the third-party apps for Google Music) is definitely not happening. Music downloaded from Amazon MP3 doesn't count against your 20,000-song limit or your Amazon Cloud Drive storage, and neither does any music uploaded. I also uploaded my entire library to this; again, it took about a day over reasonably fast internet. Itunes Match Itunes Match is the newest and most featured cloud music system. Not only can you upload any kind of music, it will also up convert your files-no matter where they are from-to 256kbps playback. The technical aspects are more in-depth than Google and Amazon's, too; instead of simply uploading everything, it looks for tracks in the Itunes store that match what you already have and adds those instead of uploading everything you have. If it doesn't have it in the Store, it will upload it and convert it to 256kbps Apple Lossless anyway. If you desire to download to another computer, or Idevice, that's no problem, either; you can add up to five computers, and, I think, an unlimited number of Idevices (I already have three with Itunes Match music on them; an Ipod, pad, and phone. ). The downloads are also 256kbps Apple Lossless format. Uploading my entire music library took considerably less time than Google or Amazon, too; I'm assuming this is because of the Matching feature. Of course, all this additional capability does cost, but it's fairly reasonable, at just 24.99 a year. Naturally, it cleanly integrates into idevices-the Music feature on Iphones & so on simply shows a little cloud icon next to the song/album/playlist, and doesn't if you've downloaded it. So, this is what I've experienced; anyone else care to contribute?