Currenty we have Support as Follows:

Billing:
E-mail & Ticket System built in MB

Support:
E-mail & Forums
Soon to be integrated: Ticket System & Chat

My customers don't post on the forums but they regularly state they check the uptime and like the idea and they regulary check the network news and such as well on the forums. Overall everything I am currently using, the customers love. I did an individual one on one survey on a few customers who didn't mind me contacting them relating to quality support and I asked them what other things they would like to see; the majority stated a ticket system with only 10% stating they wished to see chat software and 5% asking for phone support.