Okay, I trashed iTunes, re-installed from a clean .dmg file and now the devices show.
Unfortunately, I'm now getting the oh-too-common non-syncing issue (an "apply changes" gets the spinning gear as it tries to start synching and then I eventually get the "could not be synced because the sync session failed to start.") This holds true for both devices.
Nothing has changed that would affect the way the iPad is recognized in iTunes. Here is the link to Apple's support article on this issue.
You probably have done all of these steps except for....
Mac OS X v10.6.8 or earlier only: Reinstall the Apple Mobile Device Service.
Here is another troubleshooting article that might help.
Update: Upon restart today, the devices had "disappeared" again.
Thanks, Demo, for the second troubleshooting article linked above (http://support.apple.com/kb/ts3540). I went through it and did the first set of steps (1-6) and my devices are now there.
Unfortunately, the iPod Touch (not this forum, I know) still hangs on syncing at "Step 6 of 6: Waiting for items to copy" and the barber pole slides on interminably...
Everything has synced (I check it on the iPod) but it never gets beyond that message in iTunes. I believe others are having similar problems. If it's not one thing, it's another...I'll be happy when the bugs get ironed out of iOS 5 a bit more.
But with Demo's great help, at least I can "see" my devices again. Mahalo!