I can speak for the framework part, since it's what I'm mostly into. Having parameterized tests is something very useful in some cases, although something other frameworks have had for some time.
The assertions part is what I prefer, since with the constraint model you gain a lot of expressiveness, and the 2.5 release has a lot of new assertions as well as modifiers to customize them to some extent. Furthermore, having modifiers accept inline methods is great for the million times when you have to compare two objects for in/equality and you want to override the concept of equality those objects have in your domain.