iPod and iTunes here too.
One thing that's really impressive is that, unlike the Rio Volt, the iPod has an ultra low noise floor, even when cranked all the way; you can really tell when listening to a clean, quiet aif or wav. With an mp3 that soft whine in the iPod's mp3 decoder spoils it. I'll be really glad when Apple comes out with a patch for that. It's not too noticeable with the iPod earbuds or Sennheiser HD 600's, but with Etymotic ER-4P's it's really annoying. iPod owners: If you haven't done it yet, find an ultra clean CD track with lots of quiet or dead air (i.e. a slow solo) and rip it to .aif (or .wav), then encode that file to mp3, load both to your iPod and compare. The aif or wav has no whine.
Also, I'll be glad when Apple comes out with a patch that allows you to sort on the iPod by "Genre->Artist->Album->Track" instead of just "Artist->Album->Track".
The guts of iTunes is SoundJam MP. I still use SoundJam for rip/encoding because it gives more control over some encode parameters. And although I use MP3 Rage for most tag tasks, the Album Manager 1.8.1 plugin for SoundJam offers two indispensable functions that really save a lot of time when needed -- the "Tracks" command & the "Pull Track Names from File" command.