Last.fm is what I have been using the most, and my last.fm profile is here. It combines stats, with a recommendations / social networking aspect.
There is now a new one called iLike on the scene, and so far I really like it. One thing that was missing from last.fm is that it didn’t analyze your listening habbits prior to installing it, so it only showed stats going forward. iLike actually takes the time to analyze your entire library, looking at which artists you’ve played the most and which songs you’ve played the most. It doesn’t do an analysis of your ratings, like iTunes Registry, but that one is a bit of a pain as you have to upload your iTunes xml file manually, whereas iLike does everything once you install it, and continues to update your profile as long as you keep listening.
Here is a snapshot from my profile showing recently played songs, top artists, and top songs.
Here is a link to my iLike profile.
Another thing that iLike is missing is the “weekly top artists” that last.fm keeps, but last.fm only keeps the last weeks information. I’d love to be able to go back to any day, week, or month in time, to see what i was listening to way back when.
iLike also let’s you hook up with friends that use iTunes and iLike, and it let’s you listen to what they listen to. I don’t have any iLike friends yet, so I haven’t been able to use this feature. I just installed it a couple of days ago, but if you are reading this, and you use iTunes, give iLike a try and let me know, so we can hook up.
As far as the recommendations, it does a couple of things. First, it shows other users that have similar listening habits (even if you don’t know them) and what they listen to. Second, it shows songs you may like, and let’s you listen to them. Some of them are even free MP3 downloads, so that is pretty cool.
So far, it does seem to slow things down a bit in iTunes, but I haven’t really spent that much time figuring out if that is the case — it could be that I recently got iTunes 7.0.1 to actually work. But that is my only complaint.