Google Talk Chat/Conference Solutions
It appears that I may need to design my own. There is a Python project named Palaver which implements nearly everything, so it may be that I need to do very little coding:
palaver is a multi-user chat component for Jabber and XMPP servers. The intention is to support all features of XEP-0045 as well as the relevant extended discovery features of XEP-0128.
...
Currently all basic multi-user chat features are supported, including some extra things like ban lists. More features are on the way, and the intention is to fully support the entire protocol. Specific information on protocol features can be found in source:trunk/XEP.txt#latest. There is also Plugins support for extending different features of palaver.
It is more than what I want, and I haven't dug into it yet, but it may be a nice, quick, and easy fix. Although it looks more like a plug-in that goes into the jabber server itself, so it may not be suitable, and if so I'll just port the existing confbot to Twisted Words.
-Adam
You can also use Google Talk Labs edition desktop app which supports conference. But the problem is it's text only.
Partychat — "Create chat rooms with your friends or coworkers using Google Talk or XMPP."
Meets many but not all of your requirements.
- Supports Google Talk: yes.
- Free and open source: yes.
- Runs on Windows: if you run it in AppEngine's SDK's local dev server.
- Implements basic functionality such as kick/ban, emotes: somewhat; commands include /kick and /me.
- Remembers who joined the conference room across restarts: yes.
- Obeys Do Not Disturb and Busy status: nope, although you can /snooze to squelch it for a while.
- Archives all activity: nope.
Why not just use the Google Talk Gadget? Doesn't meet all of your requirements but does allow you to create a conference chat with you Google Talk buddies...
http://talkgadget.google.com/talkgadget/popout