You guys with the phat models (prior to the slim) should be fine. From the looks of it, most, if not all, of the PS3's fixed themselves.

One thing you can do for sure however is load up your ps3, deactive the network, reconnect again and check if u sign in. If so, load up a game then quite it. Then resynch trophies and all issues should be resolved. You may not have to do this however as all I did was turn my Ps3 on and everything was just as it was. My date and time is off slightly, but that was fixed with updating it via internet.

Yea mines back to normal
Look at the shitstorm that was created from 24 hours without PS3's worldwide, haha