I substituted mizuna for the arugula this time around and everything turned out just fine. The mizuna in fact was not as flavorful (translated peppery or even as bitter) as the arugula. I didn't like it quite as well, but Curtis said he liked it better. (The recipe was posted earlier....if you can't find it, use the butternut squash or arugula label and it should be easy to find).
The squash was just as wonderful as last time. Not quite all of it made it into the pasta because it was done before the rest of the dish and I found myself snacking on it occasionally. What a tasty snack!