This is a completely different type of sailing but WOW! That is fast. I wasn't really all that interested in the kite sailors breaking speed records because I don't see that as the same sport but this, although completely different than the sailing we do, is more likely a sailboat.

"Ok mental speed,s!!! On the GT-31 gps 67.74 and an average 500m 65.37! Yihaaaaaaaaaa..." http://www.sailrocket.com/

There are a bunch of Youtube videos if you want to see a crazy fast sailboat.
https://www.youtube.com/watch?v=dokkkqBcyPQ
https://www.youtube.com/watch?v=wnjyusAgk8I
https://www.youtube.com/watch?v=sZVIj5TUSKE