Pidgin is a powerful open source instant messaging software that supports multiple protocols. Pidgin has a redesigned interface with new avatars and optimal management system status. Pidgin adds smooth scrolling functionality to universal friend avatar management and conversation windows.
About gtalk and QQ support: The pidgin I use shows that it supports the QQ2006 Lunar New Year version (not sure if it only supports this version). In addition, pidgin can show whether others are invisible.
Pidgin supports XMPP, the predecessor of XMPP is Jabber, a network instant messaging protocol produced by an open source organization. There is no support for XMPP in the official Gtalk help. I tried to log in using the Jabber-supported method provided by Gtalk, but the login was unsuccessful.
You can use SILC (Secure Internet Real-time Conference Protocol) to log in to Gtalk, and you need to accept the public key. In my test, I could only successfully log in to one Gtalk account.
