The ASP.NET part is what has me excited - it wasn't clear from the article (it may be due to my limited knowledge of the ASP.NET stack) but if I could write a full fledged ASP.NET app on Linux using the often needed features like ORM, LINQ, whatever the equivalent of JSF is - that would be a great development. Right now on *NIX platforms nothing matches the maturity of Java/J2EE.
It still remains to be seen how much the of the tooling - debuggers, profilers, deployment tools etc. will be available on non-Windows platforms. May be that will become available as more and more people start using it in Production.