What about QoS over public Internet?

I heard that Ipv6 will make bound of two worlds – flexibility of datagram subnet (Internet) and quaranty of quality that provide virtual circuit subnet. Is this true? Will this (at least technicaly)in future can provide QoS over public Internet even for business critical aplications? Or if not IPv6, which factor can affect that it future Internet can become primary network platform for business critical aplications?

Or you think that it is not only technical factors, but economically and politically, because with this solution a large service providers will lose huge profits that
they realize by providing services such as MPLS