K-64 is simply 4x K-16 period. They even have connectors for this very purpose fitted onto the K-16 reference design.
Yes, you can "hook" the K-16 boards together in an array. However, The developer BKKCoins himself has said that he will start work on the K64 board as soon as the K-16 is complete.
https://bitcointalk.org/index.php?topic=190731.0Yep, time will tell. It's my understanding that the K64 is on one card, containing the logic of 4 K16 plus overheads. Just wondered how
just-in-time Terrahash will be?
I'ld ship all chips I had as K16! Not hold back any, until the shipment of chip immediately before I thought the K64 was ready.