IPv6 Address allocation best practises for sites.

Question about what other service/network providers are doing in relation to allocation of addresses for websites. With IPv6 starting to trickle its way in, what is considered the industry best practise now for IP(v6) addresses bonded to websites. In the past the standard practise was to have a single IPv4 address shared between multiple sites using a name based virtual host directive in Apache/IIS, unless of course the site was SSL in which case it normally needed a IP of its own (unless you had a client who was happy to only support SSL on IE7+ browsers with SNI). Does the best practise switch to now using one IPv6 per site, or still the same one IPv6 for multi-sites? - Mitch