One of my wish list for Google Talk is now available in Gmail Chat. Gmail Chat has added the invisible status option. This feature is available in the new version of Gmail, supported in Internet Explorer 7 and Firefox 2 or later. This works in Google Apps mail chat also, provided the new version is allowed by the administrator.
To change to invisible status, click on Set Status Here dropdown below your name in Gmail Chat and select invisible form the list. So now you have the option for setting status as visible, invisible or busy. Gmail Chat remembers your status when you login next time in Gmail.
This feature doesn’t work if you have Google Talk desktop client or Google talk gadget running. Google Talk client still does not support invisible status mode yet. It is said that Gmail Chat is the most used interface for Google Talk. Let us hope that Google will soon add these features to the next release of Google Talk client.
If you are in invisible mode, you will not be notified of your friends request to add you to their friends list. I hope this will be fixed in soon.