(SMC Reset tip for Devices not recognized after update)
"Did anyone else have problems with the Thunderbolt 1.2 update?
I did - after the update my Display and Thunderbolt drives were not recognized. I had to do an SMC reset - several times - before I could get everything going again.
Just wondering if anyone else had any problems?
-C.
MacBook Pro (15" Late 2011), OS X 10.8.3, 16GB RAM, 512GB SSD, TB Display"

Some others also had the same problem (devices not recognized after the update) and the SMC reset tip helped, based on later mails (thanks Simon, Tim, JC) and thread.

And a mail from a reader about problems installing:

(problem report, with later update comments)
"Thunderbolt update
Tried to do it by apple update, Then showed the two. (Showing an earlier TB firmware update version also?) Tried each one! Still shows. Even downloaded the update and tried that way!!! Still shows needs! I was also going to log into apple communities and now my user name is no longer good! LOL.
I have a MBP Late 2011 ID 8,2 2.4ghz, 16GB ram, 750GB Drive, OS X 10.8.3.
Guess I am not the only one with this issue on apples site but not able to log in.
HOPE SOME ONE FIGURES THIS OUT! ;)

* Is the MacBook Pro running on AC power? (Doc notes won't install if on battery).
* Did you ever see the update actually applying on a restart? (status/progress bar filling in, etc)
* What's connected to the Thunderbolt port? (if anything non-apple, try disconnecting it.)
* Maybe try a safe boot/repair? (I remember there were problems with firmware updates working from raid volumes but doesn't look like you have a raid setup.)-Mike)

(he later wrote)
I did try the SMC reset. which still was a failure. to show updated.
Yes I was on AC Power.
Yes it showed as if the update was applied. and restarted each time.
I had the thunderbolt port with with nothing connected several times I even tried with my Echo ExpressCard Pro Thunderbolt Adapter. Thunderbolt Express Dock which failed also.
I then tried Again with nothing connected failed.
Each time Like I said it showed as if it were installed.

So had to go to a open house. (that time of year) So disconnected the power. (Can't pull battery) shut down. came home about 4 hours later started up. and ran the software update and it showed it worked! Guess for the silly enough part it just needed to shut down for a while. guess it was tired.

But weird. shows all working updated now.
-Gary"

Strange, but glad it finally worked out. Thanks for the follow-up.

Checking apple's forum I found a recent post in an older thread on Thunderbolt Firmware Update 1.0 still showing on Software Update after installed. A May 11th (today) reply:

" After 5 unsuccessful attempts, this did the trick for me. Unplugged my non-Apple display from the miniDP port, and the f/w update was applied after the next reboot.
-P"

Of course not everyone had a problem with this update, the above posts/tips are just for those that did. I've recd some mails on no issues seen (including a 10.8.4 beta user). On Saturday I applied the update (download updater) on a late 2012 mini (MDP cinema display on Thunderbolt port) without any problems installing or afterwards. (MDP Display and USB keyboard/mouse and Superdrive connected to it were all recognized after update.)

Update: If you've had problems with the Thunderbolt firmware update 1.2 reappearing/not installing or problems with thunderbolt ports not working after the update, see this apple support doc from our June 19th news page: Thunderbolt Firmware Update 1.2: Keeps reappearing and Thunderbolt ports and Target Display Mode may not work.

• Belkin Thunderbolt Express Dock Review
• More Tips on how to solve greyed out volume control
• Apple deluged by police demands to decrypt iPhones
• Apple's iRadio Royalties Problem

• Runaway applications can shorten battery runtime, affect performance, and increase heat and fan activity
  
  (updates from Saturday follow)
• Understanding your support coverage and service options
• Supported router devices for Back to My Mac
• Some third-party devices may not see 5GHz AirPort base station Wi-Fi networks
• OS X 10.5 Leopard: Information to collect before an Erase and Install
• iSync: About third-party mobile phone plug-ins for OS X v10.4, 10.5
• Boot Camp: System requirements for Microsoft Windows operating systems
• Trouble installing iTunes or QuickTime for Windows
  
  (following doc now archived/no longer updated)
• iTunes: Music Sharing does not work if Firewall is on

• 9th Annual HDTV Shootout at Value Electronics (video stream)
• NuGuard KX Kinetic Energy X-Orbing iPhone Case Finalist In 2013 Biz Awards
• Virtualization's forgotten feature: Short reboot times
• '24' Eyes Return As Limited Series On Fox
• Getting to Know Your Surround Receiver
• Samsung ES7500 / ES8000 TV US Firmware Update v1051.2 (see DL/FW tab)
  (reportedly new chgs are Netflix and Evo kit related, rest of list is previous/repeats)

Thursday May 9th, 2013 News Archive
• Thunderbolt Firmware Update v1.2 (Info/Download)
• GripStand mini Protective Case & Desktop Stand for iPad mini (sponsor blog)
• PCmag guide: How to Run Windows on a Mac
• Review: B&W Z2 AirPlay dock
• Updated Apple Support/How-To/Troubleshooting Docs:
  - iMac (27-inch, Late 2012): Installing or replacing memory
• Other News/Reviews/Tech/OT:
  - Seagate 600 Pro Enterprise SSD Review
  - NuVo Technologies Wireless Audio System
  - Review: Spears and Munsil HD Benchmark, Version 2
  - BlueStacks Brings Android Games to the TV Via GamePop Console
  - Warner Archive Instant Takes Back Titles From Netflix
  - Review: Seiki SE50UY04 4K HDTV ($1499)
  - What's Wrong With the U.S. Job Market?
  - Tech Trends 2013: Video

For links to older news pages, see the Archives.