A few days ago, my Google Talk client somehow lost the ability to display the text in the chat window:
Seems that someone already asked for assistance regarding this issue back in 2010 received no answer: http://productforums.google.com/forum/#!msg/chat/DenwPvMrFrU/iEGxvdnzD-0J
I uninstalled and completely purged the Google talk software with Revo Uninstaller. Next, I rebooted. Then, I installed Google Talk with the latest version. The problem persists.
I am running Windows 7 x64.