I think the major advantage the iPhone has over every other mobile device is the iTunes environment. It doesn't really matter how great the hardware is on the other phones, the ease with which you can plug in your iPhone and one-click sync all your digital media from one interface is hard to beat.
I have the Motorola Droid, which runs the Google Android OS, and one of the major frustrations I had was that to manage music, pictures, or video, I had to mount my phone like a USB drive and click and drag anything I wanted onto or off of the phone, which can take some time if you're working with several gigabytes of media(the Droid comes with a 16GB card).
doubleTwist is free software that is an attempt to bring this convenience to the rest of us who don't use Apple's phone or mp3 players.
It looks very similar to the iTunes UI. Here's a screenshot from the doubleTwist website, click on the pic for a larger view:
As you can see on the left under the "DOUBLETWIST" heading, you can search and subscribe to podcasts.
Click the "MUSIC STORE" link, and you'll find that doubleTwist integrates with the Amazon mp3 store, where most of the time you'll find music much cheaper than on iTunes or Zune, DRM free.
In the "LIBRARY" menu you'll be able to view and manage the digital media on your machine. doubleTwist also allows customizable playlists.
In the "PREFERENCES" menu, you can change media locations, set to automatically sync when your device is attached, or set custom syncs for only the media you want moved to your device.
doubleTwist is worth checking out if you use your mobile phone as your main media player, and have more than a few GBs of media to manage. It has a very light learning curve if you're at all familiar with iTunes.
You can download doubleTwist beta for free at the doubleTwist website, and it works with Mac or PC.