Which way to happy camp?

Went to back up my iPad on iTunes and was offered an upgrade of iTunes software.

Like a dunce, I accepted.

Now iTunes won't establish a session with my iPad, and without establishing a session, no backup is possible.

The only online help I can find talks about deleting the photo cache, which I've done, but turned out to be a waste of time.

I've rebooted the iPad several times, also to no effect. I've deleted previous backups (great advice, huh?), with no joy.

And of course, it's not as if you can plug the iPad into another "authorized" computer and back it up there, because the only choices you're given there are to erase the contents of your iPad or transfer purchases from it.

Word is that iOS 5 makes it possible to dump iTunes completely.

I can't wait.

But first, I'd really like to back up my data.

Cheers...

UPDATE: Apparently, I'm not alone with this issue. There are a number of messages that are variations on this theme in the Apple Support Communities.