Would love to look at some screenshots and judge usability.
But it's hugely appealing that 1. It's written in Scala. (A language I am familiar with) 2. It's packaged as a single file; download and run. I like single file installs. YouTrack by JetBrains is another example.
MTS is a topic unto itself. Check out this for example: http://mbeddr.wordpress.com/blog/ An Embedded C DSL, built using MTS.