Depends on what you want to use it for. From what I can tell, the Zune HD is better if you just want a media player while the ipod touch had apps and all that.
I have an ipod touch but I only really use it for games or movies and for me it's something I need to plan to take with me. For listening to music, I still use an old ipod nano because it's small, has a good battery life, and does what I need it to do. That said, if they released an iphone with a good battery life, I'd ditch my cellphone and mp3 player for it. It's not so much that I have anything against the ipod touch, it's just not a very useful device for my purposes. I've since learned my lesson and won't buy the ipad...also because that thing is crazy expensive.
and itunes is awful on PC. It has like four background programs running even when the main program isn't. All I want to do is plug my device in, throw music, movies, or apps on it. I don't do that daily or even weekly, so fuck having things constantly running so once in a while I can use the device I payed a couple hundred dollars for. It's true that the average person doesn't mind this stuff, but they're the ones who download Bonzai Buddy and violate their computer.