Jeremy Miller has done a great work on Fluent NHibernate (and here) that offers strong-typed nHibernate mapping configuration, requiring absolute ZERO xml! You will get all the type-safetiness, significantly reduced noise, convention-over-configuration simplicity, seamless bootstrap to IoC, and it even offers a set of library that allows you to write unit-tests for your mapping config. Yes, imagine it… TDD-ing your nHibernate configuration with test-first approach!
Combined with Ayende’s work on Linq2nHibernate, apparently we have now been to the point where it takes nothing but all strongly-typed C# code to get full capability of an ultra powerful ORM technology like nHibernate.
Live without XML and SQL/HQL string, oh what a wonderful world.