Why are all contacts grayed out in Google Talk? I have just noticed that all my contacts in Google Talk are grayed out. I can't chat, see their online status or otherwise use the app. What happened? Any suggestions on how to troubleshoot or fix this?

I have a Nexus S. I don't use Google Talk often, so this is the first time I have noticed the issue. There were a couple of recent events that may be related. A few days ago I received the official Android 4.1.1 Jelly Bean OTA update from my carrier (I previously had 4.0.4 Ice Cream Sandwich). Also, there was a major Google Talk outage that affected most desktop and mobile users.

I searched around and found possibly related reports, but with a few differences. For example, I don't have settings for turning off data usage. Also, I can correctly use Play Store and other Google apps. I cleared the Google Talk cache but nothing changed.
I did some tests, and turns out that the contacts are grayed when your phone's APP isn't able to communicate with Google Talk servers.

This is also the behavior when using Google talk on other systems, or even from Google web pages, like Google+.

You didn't noticed this before, most likely because you never had a communication issue with their server, witch is good. I have my grayed contacts all the time :(