Had a horrible day trying to backup and restore my brand new iPad, because iTunes is just about the WORST application for Windows, ever.
iTunes has reported my iPad as non-existent or only having 4Gbytes of storage (it's a 64GB model), and the apps sometimes just do not work after a sync operation (tap them, they open up and immediately close). ALL of the installed apps have had this behaviour, and iTunes says my ipad cannot backup due to various internal errors with weird numbers like -54 and -48.
Someone (somewhere) suggested using different USB adapters or ports, so I switched to using ports on the back of my (November 2009) computer instead of the front, which has (surprisingly) made a huge difference.
Had a lot of trouble getting Kindle App to work , because the keyboard defaults to capitalization of first letter, and Amazon has CASE SENSITIVE email addresses, sheesh. Took me a long time to sort out that.
the iPad itself is very very good when it's working. iTunes is so unreliable on Windows I'm honestly surprised it can be used. Awful awful application.
It makes NO SENSE to my why I need to jailbreak my iPad to use a wifi-sync utility instead of being dependant upon a cable tethering the iPad to my damned computer!
Wifi sync just makes incredible amounts of sense, whereas usb sync (when the PC can't supply the 'double wattage' to charge the ipad) makes VERY LITTLE sense.
I got Air Video working, and it's simply stunning to watch ripped DVD's over wifi, stunning.
So in closing, a huge thumbs up for the iPad, and a very very large thumbs DOWN to iTunes.
(I hope this message doesn't get censored)