IPv6, like any new technology, takes time to implement and operate. Here are some tools to make checking, tracing and verifying IPv6 easier for you.
For IPv6 connectivity, providers must set up IPv6-addressed nameservers, AAAA ('quad-A') address records, AAAA mail exchange records and allow website access over IPv6.
If a host sends IPv6 packets that are too big for part of its route, it should get a Packet Too Big message so it can re-transmit the data in smaller packets. If that message doesn't get back (e.g. firewalls, mis-configured routers) it can affect IPv6 connectivity.