This is completely unconfirmed, but, on the user's desktop that had this problem, I discovered that the user who had the problem was infected with a previously UNKNOWN virus (stored in two randomly named dlls) which was submitted to Microsoft and VirusTotal for classification. A few weeks later it was classified as the following severe threat/virus - "TrojanSpy:Win64/Ursnif.AK" - by Microsoft. Here's the entry for that on the Microsoft website and on VirusTotal.
Once this threat was removed and Chrome reinstalled and updated to the latest version, the problem went away. Not sure exactly how the two were related but, for this user, Chrome stopped working immediately the day after two suspicious virus related DLLs (based on their timestamp) were installed on the user's desktop.
Scans with the latest up-to-date version of Microsoft's Security Essentials caught the virus (and hopefully other anti-virus vendors have now implemented signatures for it as well).
Try an updated anti-virus scan and see if resolves your issue!
Update 9/6/2012 11:08AM: The solution below kind of works, but it is clearly only a temporary fix. If you desperately need to use Chrome, you can just double click on the old_chrome.exe and it seems to work, however, if you use the regular "chrome.exe" it may eventually have a problem again. Waiting on an official Google fix - see this post on the Google product forums.
I recently had a user who had Google Chrome, and when they opened it up, no pages were loading, and all pages (including configuration settings) appeared gray, and nothing at all would display. The user's Chrome version is 21.0.1180.89 m and it looks like it was deployed 9/4/2012 at 3:19 AM (during the night).
The gray pages look like this:
I located the folder in which Chrome is installed. In this case (Windows 7 64-bit), it was:
where <your username> is the Windows user account you used to log on.
Although it is odd and may not work for everyone, I was able to run the program "C:\Users\<your username>\AppData\Local\Google\Chrome\Application\old_chrome.exe", and it loaded up a previous version of Chrome which loaded as it was normally expected.
Navigate using Windows Explorer in Windows 7 to:
|Run "old_chrome" just once and then close the program and run Chrome as you normally do.|
I'm not sure completely why it fixed the problem (for that, we will have to wait and see what Google says regarding the issue), but it did.
Here is a related post ("Page not loading in Chrome") on the Google product forums that might help you if the fix above doesn't solve the problem for you.
Looks like a little Google bug. Oops!