"MonoRail is a compelling option because most of the folks on our team really like Ruby on Rails. The potential problem with MonoRail is its applicability to enterprise software shops. Even though there's been some good discussion on enterprise Rails, this is still that period of time where folks aren't clear on whether corporate shops are ready to let go of heavy-weight .NET and Java web frameworks.
Nonetheless, MonoRail is hard to ignore. It simplifies web development on .NET much in the way that Ruby on Rails simplifies web development period."