NHibernate is a mature and stable framework and has been around for many years. Many companies have been using it in many different projects. A lot of those projects are mission critical to the respective companies. Other applications that use NHibernate are exposed to high load and perform very well under these stressful circumstances.
Due to political reasons, not all companies wish to disclose their usage of NHibernate.
However, there is still a list of success stories available on the NHibernate website. This list can be found by using the following link: