ticket system is a must to really track what is happening
Live chat is excellent as customers are global and this makes it easiest to chat with people regardless

I have to agree on ticket system with email piping, that's what we do.
And we only provide chat and phone for sales issue.

Email piping to a ticket system and live chat when clarification or discussion is needed.

I prefer a ticket system using a web-based interface for creation and replies with an email notification that the ticket has been created/responded to. Most clients seem to prefer email since it doesn't involve a username or password. However, email is subject to mis-direction into a SPAM folder or being deleted by mistake. Another problem is that clients may use an email account that belongs to the hosting account that is failed, so the email may not be sent or received.

I voted for Ticket system and live support

I think ticket system with direct email is the way to go. Forum support systems end up with way to much junk in them and are confusing to find the right answer. Phone and to a lesser extent live chat are hard on reps. While I was doing customer service for cell phones there was a routing issue and my line was getting fed by some escalation line. After de-escalating 35 consecutive calls I asked my supervisor to take me off the phones because if Mother Theresa had called then I would have told her to go to h***. They managed to fix the routing issue while I was scowling up and down the halls and I managed not to say anything that would cost me my job.

I prefer support ticket system. Easy to keep track of. Phone support is taking too much time and money especially customers are not paying much but demand much.