We had a (re)naming competition for the language, and Wasabi came in second. The winner was actually Bone Crusher 3000. http://blog.fogcreek.com/the-origin-of-wasabi/
Thistle -> FogBasic -> BC3k -> Wasabi
See, right here you can see HN always picks the wrong things to be outraged about.
Coffeescript has a similar name to Javascript, so you can quickly draw an association between the two.
The name Wasabi doesn't have an obvious connection to the VBScript that it's based on, which seems to be the cause of people talking about writing a whole new language, etc.