In IPv4 land, you could probably get by with a single feed and see the entire internet. Of course you would not have any redundancy, but apart from the odd spat and peering fight, you could get to everything. In V6, not so much. Of the 3 transit peers I have, the numbers range quite a bit. AS174 is missing about 20% of what AS6939 and AS6453 has. There is idle gossip on http://nanog.org as to the reasons… but there are still some 500 /32s (ignoring more specific /48s which might be reachable through the /32)
eg
11647 6453 293 11647 6453 701 668 11647 6453 30071 13645 11647 13030 15716 11647 6453 5511 11647 6453 6762 5609, (aggregated by 5609 163.162.170.129) 11647 6453 6830 11647 6453 25137 11647 6453 30071 4608, (aggregated by 4608 203.119.76.3) 11647 6453 30071 2549 11647 6453 30071 10318 11647 6453 6762 7303 11647 6453 30071 11647 6453 6762 8280 11647 6453 13030 11647 13030 11647 6453 701 11647 6453 6762 11647 6453 5511 8346 11647 6453 30071 11647 6453 13030 8271 11647 13030 8271 11647 6453 13030 33845 11647 6453 30071 4608, (aggregated by 4608 203.119.76.3) 11647 6453 701 18061 9555 11647 6453 6762 7642 11647 6453 30071 6536 11647 6453 701 18750 11647 6453 30071 19151 11647 6453 701 26773 11647 6453 30071 10326 11647 6453 30071 19151 16842 11647 6453 30071 19151 31877 11647 6453 30071 19151 22911 11647 6453 30071 13911 11647 6453 30071 7786 11647 6453 30071 13911 14595 11647 6453 6762 7303 4270 11647 6453 6762 7303 4270 27770 11647 6453 6762 7303 4270 5692 11647 6453 13030 48218 11647 13030 48218 11647 6453 13030 20634 11647 13030 20634 11647 6453 701 12702 24807 11647 6453 6830 11647 6453 5511 8697 11647 6453 6762 31463 11647 13030 9191 11647 6453 13030 25164 11647 13030 25164 11647 6453 13030 16242 11647 13030 16242 11647 6453 13030 28717 11647 6453 13030 25563 11647 13030 25563 11647 6453 5511 3215 11647 6453 5511 3215 11647 6453 5511 3215 11647 6453 5511 12493 11647 6453 13030 44573 11647 6453 13030 35366 11647 6453 13030 29430 11647 13030 29430 11647 6453 13030 21232 11647 13030 21232 11647 6453 13030 47617 11647 13030 47617 11647 6453 6830 20825 11647 6453 6762 8953 11647 6453 13030 15216 11647 13030 15216 11647 6453 13030 11647 13030
For a full list of /32 routes, see ipv6-routes-missing.txt
BTW, there is a cool tool at
http://www.sixxs.net/tools/grh/compare/ which can give further information/views