There is no REAL reason why this should happen after an update, but it is not the first time someone has said something about it.  The only thing that would cause that, was a problem during the BR-D firmware update, if there was one.  Apparently, there may have been.  A SYSTEM update should not cause that to happen unless something VERY wrong happened during the update...    That something would also have be a marriage problem with the drive to the console, may have been, for lack of better analogies, annulled...  Then again, that should only cause game discs not to work, all other media should work. 

You will either have to bare the no use of the PS3 till the next update to see if that fixes it, or have to get another one if no one will help you at Sony... 

Or, it is just coincidental that the laser diode blew after the update, as of no consequence to the update, it was just a coincidence. 

There is nothing you can do to get it out of that state except waiting for a new firmware update and see if that helps.  Since you have no warranty, and can't do anything about it, you can take 'er apart and check to see if the laser diode is working...

If it will ALLOW a reinstall do it, but if it went through all the way, then it won't allow an install again. 

It has nothing to do with PCBs and Electronics, you just open it up, power on and see if the little blue-dot is in the laser lens. Do not look DIRECTLY down at the lens, it can cause harm.  Turn the lights off if you have to, and see if you see the laser...   There are dissemble instructions somewhere...