It's a poor design to have the minimum subnet be 2^64 addresses though. 2^48 addresses for all Ethernet devices in the world hasn't turned out to be any sort of problem and it's only recently that 2^32 IP addresses for the entire world became a problem (and things still work reasonably well even though almost no-one is IPv6 only).
70 trillion possible vendor allocated MAC addresses (46 bits), and currently 7 billion people on earth. 10000 each. I suspect that will be enough for now, but they never get reclaimed (AFAIK) so they won't last forever. This article discusses some of the merits of the 64 bit subnet address - http://etherealmind.com/allocating-64-wasteful-ipv6-not/. I almost stopped reading when I read that "IPv6 addresses are 296 times more numerous than IPv4 addresses" until I realised that they meant 2^96. A lot of these arguments end in the circular statement that "subnets are 64 bits because SLAAC is 64 bits", so I'm yet to be convinced. James [1] do/did Bluetooth and token ring addresses come from the same pool? Google wouldn't tell me with any certainty