This is what I did. I don't know if this is the only or best way to change the computer you sync with, but it seems to work. Use at your own risk - please make sure you backup everything first.
I followed the instructions
here to make a copy of my itunes library on another computer. One of the steps is to use this utility which copies all the files. It was hard to download the utility - iTunes Library Mover. The link takes you to an error page. Interesting enough, I was able to access this file from my iPad using safari and I used an app which reads .zip files to mail it to myself. I had to first change the extension to something other than .zip (like .zipp) because the iPad mailer doesn't seem to like attaching files with .zip extensions.
So after I did all this I had an exact copy of my music/videos on another computer. Also, since I authorized the other computer with my account, I was able to transfer all the purchase licenses.
So I held my breath and "sync"d the iPad. It says it will erase and resync. It actually only erases, music and videos (as far as I could tell). It left all the apps and photos untouched. When I sync'd it erased all the music/videos, but since the new computer now had all my content, it just brought it all back.
I had some issues with album art being messed up and stuff.. but I'm not sure if that was due to some other mucking around I did.
In any event, I successfully got it to sync on the other computer and the iPad is pretty much none the wiser.
I'll report back any issues.