That's right - RikWik: Goomburra is finally available.
Goomburra is a Wiki engine written entirely in ASP.NET. It has a number of features that set it apart from existing Wiki solutions, particularly in how extensible it is. It's also open source under a BSD license so go grab it and give it a go.
I've opened up this page so you can give Goomburra a go online. You have full permissions to edit the page, change the skin and generally try things out.
All the details are on the RikWik page including the (abbreviated) feature list.