I seem to have become an early adopter. I had to grab iTunes 9 as soon as it "dropped" this afternoon. It took me about 25 minutes to download the 82 Mb installation file and roughly two minutes to install it. I launched iTunes and after the usual licensing page it went into "updating iTunes Library" mode. I had left my Time Machine backup disk connected to the laptop, and while iTunes claimed to be updating my library, my Time Machine disk was running. I didn't pay much attention at first, as Time Machine regularly backs up the disks during the day. But after 10 or 15 minutes and no change in the status, I took a chance and forced iTunes to quit. Then I disconnected the backup drive and re-launched iTunes. This time iTunes came right up. It must have detected a copy of my iTunes library on my backup disk and started to organize it. That's bad, iTunes. Leave my backups alone!
There's a slightly different look and feel to the interface. The icons along the left side have subtle changes. The smart playlists now have a gear icon instead of a note, so it's clear from the icon and the color that those playlists are different. The list view shows artists on the left and songs on the right, and the grid view has a white background instead of the older dark gray background. You can change the columns in the list view, and you can switch back to the older view with the columns on top. I'll have to play with it for a while to see which way I like it. The Podcasts page mimics the iPhone podcasts view by using a half-filled circle to indicate which podcasts you've listened to only in part.
More importantly for me, there's also an iPhone update to version 3.1. There are some video tricks and MMS enhancements in there, but the feature I like most is the ability to drag and drop your iPhone apps from iTunes. When the iPhone is connected to the computer, the Apps page shows you all of your iPhone apps by the "page" on the iPhone. You can move apps from one page to another and remove apps from the phone with the mouse. Now I can roughly organize my apps by type: one page for music-related apps, one for productivity, one for restaurants and movies, and so on.
Apple also introduced iPod Nanos with video cameras, updated the iPod Touch line with new hardware with more memory and faster video chips, and bumped the iPod Classic to 160 GB. I should say that they bumped it back to 160 GB, because I own a 160 GB Classic I bought two years ago. But this new Classic uses a one-platter hard drive, so it's thinner. But it's good to know that Apple still has an iPod for geeks like me who want to carry around all their music. And if my old Classic dies, I can replace it without spending too much or sacrificing space.