For those of you who do not know this already - Feature Analyst is not only available for ESRI's ArcGIS platform but also for ERDAS Imagine. (In addition Feature Analyst also work in BAE's SocetSet, RemoteView and GeoMedia).
All of this is possible due to the innovative Feature Analyst 4.x API that Feature Analyst and LIDAR Analyst are built upon. It allows you to code once and be able to deploy your GIS tools across all the platforms that the FA 4.x API supports (right now the list is ESRI's ArcGIS, BAE's SocetSet, Intergraph's GeoMedia and RemoteView from Overwatch - our parent company). The FA 4.x API is written using the .NET framework from Microsoft - so it allows you to rapidly write plugins in C#, Managed C++ and VB. You can also leverage native C++.
Here is a recent post on Feature Analyst for Imagine: Geospatial Imaging: "Trend": Detection of form at Leica Geosystems .... (translated via Google from French - original link)