If you're routinely syncing to the same computer the way the majority of users do, they're right. Your situation, as you've outlined it to us, isn't that way. Again, the functionality you want is built into iOS 5, so in a few weeks when that's released, this should be pretty easy.
And under the "unsolicited advice" column--since you're going computerless, you might want to be selective about the apps you routinely use. In your case, it might be best to take the time to search out apps with built in cloud backup functions to services like Dropbox, and sync mechanisms between devices. Phones and iPads do break or get lost or are stolen, and right now, you don't have any way to get that data back if that happens.
I don't use the built in "Notes" app, for example, because the sync on that has never worked consistenly for me. Instead, I use an app on both my ipad and iphone that can sync with either MobileMe or Dropbox (your choice) to provide both a backup and keep content current on both devices. I use MobileMe to sync my iCal and Contacts as well, and my To Do list app has an auto sync function through a web server. I have a photo transfer app that will move images from one device to the other via wifi, and I store the really important ones on a Photobucket account.
It's not as seamless as using iTunes for backups, but then again I've lost data and images by just depending on those!
