Thus spake "Stephen Sprunk" <stephen@sprunk.org>
Someone recently posted a link (either on PPML or here -- I can't find it now) that showed ARIN's minima for the various v4 and v6 blocks. The v4 ones were all over the map, but there are relatively few v6 blocks and all of them are /32 except for one that's /48.
This is the page I was thinking of: http://www.arin.net/reference/ip_blocks.html The v6 list doesn't show explicit minima like the v4 list, but it's /32 for non-micro allocations (the block for which, unfortunately, isn't noted on this page) and /48 for direct assignments under current policy. S Stephen Sprunk "Those people who think they know everything CCIE #3723 are a great annoyance to those of us who do." K5SSS --Isaac Asimov