NHibernate Linq 1.0 has been released and is available for download alongside NHibernate 2.1. NHibernate Linq 1.0 is a remote LINQ provider that supports most operations available through the NHibernate criteria query API. NHibernate Linq 1.0 does not support group joins or subqueries in select clauses.
NHibernate Linq 1.0 is based on the LINQ provider in NHibernate Contrib, which is considered a mature, albeit limited in scope, provider. The NHibernate development team is still working on developing a full featured LINQ provider to be included in a future version of NHibernate, but they felt that the LINQ provider in the contrib project has been tested enough and used in enough production systems that it made sense to provide an official RTM version of NHibernate Linq as an interim solution.
NHibernate Linq 1.0 requires NHibernate 2.1 with the updated criteria API, but it will work with Fluent NHibernate without modification. Also, the NHibernate Linq NHibernateContext class supports the IUpdateable and IExpandProvider required by ADO.NET Data Services.