PB - Latest Apple Update Wiped - PLEASE HELP!

[HelixOmnimedia]

OH MY GOD! OH MY GOD!

My PowerBook just finished doing the latest Software update from Apple, it restared and is now sitting at a "Mac OS X Set Up Assistant"

HELP!!!

What do I do?

Should I continue through the setup? It had Leopard installed so why is it showing Mac OS X!

Have I just lost all of my data? (since October - last time it was backed up)

HELP!

UPDATE

OK, now I'm worried.

I went through the "Mac OS X Set UP Assistant" - Language, Keyboard, Registration Info, Transfer Data (none, only backed upto disc not time machine)... and then NOTHING!!

The screen flashes and then goes back to the Set Up Assistant.

I've tried restarting it... praying that it would just load to the desktop - no joy!

I've tried just Quiting the Set Up Assistant to find it just reopens.

WHAT HAS THIS LATESTEST UP DONE!!!

 

[Nermal]

The first thing I'd do is boot from your install DVD and verify your hard drive and its permissions. Is that works, then re-verify the permissions from inside OS X once you've booted back up.