Fixes	Summary
Software update	Addresses an issue that required a small number of Apple TV units to be connected to iTunes in order to complete the update.

I have an HD upgraded 1st Gen but haven't bought a 2nd gen.
  

"Not an Early Mac Pro, but my 2010 Mac Pro 12-core is having the same issue in 10.7.2; was fine in 10.7.1. After a few hours on an express lane call, we determined that my 23" ADC-connector monitor, hooked up via the Apple ADC->DVI adapter, was not well liked by 10.7.2; the Samsung 22" worked fine.

(Regarding user's tip) Unplugging/replugging the DVI cable from the card fixes the issue until the next reboot; oddly, running World of Warcraft fixes it at any time that it's past a loading screen, whether you're logged in or not, whether it's fullscreen or windowed. If you quit WoW, the problem returns instantly.
(If you run the Console app (select 'all messages' of Log Database), do you see any useful/related messages when it happens?-Mike)

Very weird. Near as we could determine, it's no longer sensing the refresh rate of the monitor correctly (60Hz, obviously, LCD panel), but unplug/replug forces it to re-check, and running something 3d makes it conform to a "proper" refresh rate as well.
(After seeing first post on the disconnect/reconnect tip that was my guess as well (caused re-detect of display). I wonder if the display prefs are getting written/updated properly.-Mike)

Using Radeon 5870 (apple stock card). The monitor is the "plastic" Cinema Display HD 23" from 2003, came with my rev.1 G5. DVI to ADC adapter is Apple's own.

There's a case open with Apple, they said they'd be running it past engineering, which could take a while. Samsung 22" 205bw works fine, connected in the cinema display's place via DVI. The issue is apparently the adapter.
(Not sure why the adapter itself would be the cause but adapted ADC displays have been noted by several with the screen flashing in 10.7.2 problem. (But they were fine before the 10.7.2 update. And not everyone has seen the problem, even with similar configs.)
The DVI to ADC adapters provide +28VDC power to the ADC connector for display power. (Originally the +28VDC ADC Display power was provided thru an ADC video card port fed from the older ADC-enabled Mac's power supply (which had a 28V output for ADC), routed to the video card via a motherboard connector that mated with a stub connector on the ADC port video card.)-Mike)
Just sharing my experience.
(he later wrote)
As a follow up, Apple called me today to let me know that their engineers have reproduced the issue in-house on the 20" and 23" ADC LCD displays (CRT ADC displays do not reflect the issue) and that it's been escalated, to be fixed in a future release.
...it's clearly a driver problem; booting over to the recovery partition (7.0) or windows 7 makes it go away. I was pleasantly surprised when they called me back, so I might hear more, you never know.
-Tom"

The 10.7.2 update reports on 'screen flashing' reminded me of the recent Display firmware update for the (Late 2008) 24in LED Cinema Displays to address Intermittent flicker while connected to a Thunderbolt port.

BTW: I've had other mails today about many other models/video cards/displays/previous OS's, etc having similar issues (going back a long time) - but the above was just a follow-up to the recent posts about some having a problem only after updating to 10.7.2.
(I realize you could fill a book with past cases of screen/display issues over years. I've linked to many related threads in apple's forums, as well as various posts here over the last decade + - notebooks, imacs, powermacs w/various cards, internal displays, external displays, cables/adapters (including apple's MDP to dual-link DVI adapter) and almost a decade ago (IIRC) one model (not apple's) of an DVI to ADC adapter had video noise problems.)

Anyway, not trying to ignore problems from the past, just a reminder that today's post is part of the recent topic about screen flashing/flicker they said was only seen -after- the 10.7.2 update. (And he says Apple has confirmed it on those ADC displays and will hopefully release a fix.)
  

• Siri? On My iPhone 4? Not Quite
• Apple Sells Over 4 Million IPhones in Debut Weekend
• 1Password 3.8.9
• Google Pulls Google Voice from App Store, Citing (iOS5) Crashes
• New Variant of Flashback Trojan Horse Gets Sneakier (intego blog)

• "Lion Recovery Update can't be installed on this disk. An error occurred while evaluating JavaScript for the package." when installing Lion Recovery Update
• iCloud: Troubleshooting creating backups
• iPhoto '11: May quit unexpectedly when enabling Photo Stream or importing photos
• Mac App Store: Hiding and unhiding purchases
• iPhone 4S: About Siri
• iPhone 4S: About Siri and privacy
• iPhone 4S: Troubleshooting Siri
• Sprint: Unable to use phone number for FaceTime or iMessage when using Google Voice
• Sprint Wireless Online Support
• iPad: Supported languages for VoiceOver
• How to back up MobileMe data
• Mac OS X: How to capture a packet trace
• Lion Server: Service Access checkboxes are inactive in Server app
• Lion Server: Push Notification Server and supported applications

• How Salt Could Multiply Hard Drive Space
• Team Fortress 2 Update Released
• Garry's Mod Update Released
• NVIDIA releases next-gen 3D glasses and monitors
• Cellphone users will be warned before hitting plan limits
• Review of UltraThin Acer Aspire S3
• Mercedes-Benz Recall Clean-Diesel Cars For Fuel Leak (Again)