How does Rowlex relate to Protege and are there other .NET offerings for OWL?

I work with RDF and OWL but until I came to SO I'd never heard of Rowlex and OwlGrinder. It's got a much larger presence on SO than Protege or Pellet (although from a smallish number of active people). Is it primarily the .NET equivalent of Protege or does it take a different approach (It stresses the Open-world assumption). There's very little on Rowlex on Google (much less than on SO) so I'd be grateful for an assessment of its role. And are there other .NET tools that are alternatives?

Quite a lot of questions. Let us go one by one.

• ROWLEX uses Stackoverflow as a support forum, because Stackoverflow is the highest quality free forum up to this date by my judgement. Hence the strong presence.
• While ROWLEX is not that young (was originally written for .NET1.1), there are only few things on Google about ROWLEX. This is because ROWLEX become public quite late. It was available as closed source product to NATO nations only for explicit request since the spring 2008. It became publicly downloadable as an open source product in May 2009.
• ROWLEX is not a competitor of Protege. Protege is an ontology designer tool primarily (according to my understanding), while ROWLEX is an SDK. ROWLEX is used both in designtime (e.g., for autogenerating ontologies or .NET code) and in runtime. During runtime, you can use it to browse or create RDF documents programatically.
• There are other .NET tools for the semantic world, but the options are not that many. You might want to look at this SO question. (Just bragging ;)