Wouhou! I feel like sharing my knowledge
As said earlier, you can virtualize in VirtualBox or VMware, it does work (you'll have to download the VirtualBox from the site cause the one in the repo does not support USB)
As for iTunes under Wine, it will load and maybe work, but the USB is not working for now.
There is also a project called iDeviceActivate that is suppose to let you activate iDevices natively in Linux/Ubuntu but I never tried it. It's been a while since I checked that project...
Also, next release of Ubuntu 11.04 is supporting the document folder of the apps on the idevices... So now you have 2 mount points: one as it was before, and another one showing each app where you can put stuff in their document folder.
But beware that with the new iOS 4.3, rhytmbox is not able to update the music list anymore. Probably a near update will fix that.
One way I figured to transfer media files on the device was to use mediatomb on Ubuntu and Fusion Store Stream on the iPad/iPhone. It will let you browse your medias on your computer and let you download them locally in the app folders for later viewing/listening... That's the way I do it even if I have a winxp box running iTunes. I don't have to connect physically on the computer to select what I need on the go...
My 2 cents!
VicoPad addict!