He's talking about customers leaving -- you're not going to lose anything.
Even if everything is fine for you now, it sounds like the real fix is Monday, so I'd just wait and see. Even if you're up now, there should be some downtime during the upgrade--but that's planned downtime.
I'm guessing that those that are back up now will probably be fine until the maintenance downtime... but shouldn't be surprised if something does go wrong, or think of it as a whole new problem.
I guess one exception to that could be if you're on a server that was already having unrelated problems that haven't been sorted out. Like the guy with the server rebooting frequently--that's not happening to everyone, so people on that one will probably need extra attention elsewhere.
Save up to $96 at Dreamhost with ALMOST97 promo code (I get $1).
Or save $97 with THEFULL97.