Is Live Chat Helpful?

I have been considering adding a live chat type feature on our website so that customers can instantly get help and have questions answered. There are loads of programs and companies out there to use at a wide variety of prices. Of course each of the companies supplying the service tells me how much it improves sales and the overall shopping experience of the customer. Not that they are bias. To get an honest answer I am putting up a poll here on our blog. Basically, I would like to know if a live chat type program on our site is something you would find useful or if it would not really matter to you because you wouldn't use it anyway. Feel free to either leave a comment or answer in the poll.