I have a hard time recommending a .Net blog engine that is comparable to Wordpress in features, ease of use, cost and polish. Frequently I'm recommending to clients who have .Net sites that are looking add a blog to just add Wordpress. This will usually require the .Net site has some complexities that aren't easily transferable (i.e. It's not just a corporate informational site with static content that is easily transferable to Wordpress all together) and that you will have reasonable control over the server environment (no cheap shared hosting environments headaches). I'm going to be attaching a blog to the APS Job Board which is a little project we are running to keep the people of Chicago (and the US) employed or employed with jobs they actually like. It's built using the latest and greatest for Microsoft web development (SQL Server, MVC3, Razor layouts, etc.). I poked around looking for some good blogging open source goodness with aspNet MVC3 and the options just aren't there or mature enough in my opinion. *cough* WebFunnel *cough* A big benefit of doing it this way it to keep the traffic with your blog and your website integrated.
