I will also be the second nunit.
For me it was not a choice. Right now I received a copy of VS2008 for free from my school, but I plan to start creating applications that will be considered commercial, so I will have to buy a copy of VS2008 Pro or higher.
So, I will use VS2008 express, which will not receive unit testing, so for me I rather stick to nunit, which is very good and saves hundreds of dollars, without having to buy Pro, since most of the features in Pro I will probably never use.
Plus many book testing units that I have seen, all use nunit.
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