However, you DO get an email from PayPal with a transaction ID, etc. That seems to show up fine, for a couple of hours, and then the link is dead. Talk about confusing... did it work, or not?
They are apparently aware of the issue and basically just told me to hurry up and wait, and that the transactions will eventually go through (hopefully within 24 hours).
So, just a heads up to anyone fielding PayPal issues today from their customers, this could be the issue.