Fortunately, there are some fairly bright people here at TUAW, and after a couple of quick exchanges in iChat, I had Genius Mixes working. If you don't have access to a Mac and iPhone brain trust like I do, you might also have problems setting up Genius Mixes, so I'm here to give you the rundown on how to do this. Read on for the rest of the details.
Step 1: Install iTunes 9 and iPhone OS 3.1
If you haven't installed either of these updates yet, you'll need to before you'll be able to use Genius Mixes. You can download the iTunes 9 update here, and you'll need to plug your iPhone into your Mac or Windows PC with iTunes open to get the iPhone OS 3.1 update.
Step 2: Turn on or update Genius
This step depends on whether or not you've used the Genius feature before. I never did; my tastes in music are such that I don't need anyone making suggestions about what I should listen to. Under the Store menu in iTunes 9, select Turn On Genius (see below) to turn on the feature. If you've already used Genius in the past, just select Update Genius from the same menu.
You'll have to agree to the terms of service, and once that's done, information about your Library is sent to Apple. When all is finally done, you're going to see a splash screen describing Genius, two new items in the left sidebar, and an active icon in the toolbar at the bottom of the iTunes window:
Step 3: Click on Genius Mixes to see what Apple has created
Step 4: Connect your iPhone and sync
When your iPhone shows up under Devices in the sidebar, click on it, then click on the Music tab. See the list of playlists below? There will be checkboxes for all of your Genius Mixes. To send those Genius Mixes to the iPhone, check the appropriate boxes, and then click the Apply button to sync them to your iPhone.
The next time you launch the iPod app on your iPhone, you'll notice that a Genius button appears (see screenshot below). In this case, tapping on it displays my Genius Mixes. Flicking left or right on the iPhone display switches between the Genius Mixes, and it just takes a tap on the screen to start playing the mix. By the way, when you tap on the Genius Mix to begin playing it, there is some fun animation of the album covers.
If you've set up Genius Mixes, we'd love to hear how they're working out for you. Leave a comment below.