Lots of very good information being shared in this conversation. For live chat to be most effective you have to make sure to respond under 15s (under 10s is ideal). After 15s about 30% of the people will drop off.
I also would make sure that the live chat only shows if you are available to chat. When you are online I also would have a proactive invitation (Hello, how can I be off assistance?). With a invitation we see a significant pick up in the chat engagement rate.
The key to an effective chat is to make sure you focus on the quality of the exchange. It is about taking the experience from a product centric event to a consumer centric conversation.
We see a chat engagement rate around 2.5% to 4% of unique visitors when we are online, about 80% convert in contact information.
This brings me to my next point, you have to be online... For this very reason we have set up a team of virtual sales assistants that are there to help facilitate the chat and convert these chats into prospects. It is difficult for a team to be available
Happy chatting!