Hi Mike,
I do not use chat and I think that e-mail would be better (albeit slower) since I rarely can participate in a chat session during the weeks while I'm at work. E-mail is "asynchronous" and because of that it works better for me.
Another possibility would be to use a forum for X2Go discussions instead of mailing lists. There are pros and cons:
Has an X2Go forum been considered?
Cheers, Daniel