Here is another video of SEXTANTE on ArcGIS. This time, I am showing how SAGA and SEXTANTE algorithms can be executed just like native SEXTANTE algorithms. This is completely true for SAGA ones, but I'm having a bit of trouble with GRASS ones, specially vector ones. This is not a GRASS or SEXTANTE problem, but just a problem caused by the strange behaviour of Java when I call the application (SAGA or GRASS) from ArcGIS, since it freezes and I haven't been able to solve it. If I execute a new interpreter (that's why the command line window is shown), it works but it returns the control back to the Java code before the task is finished. All this doesn't happen when calling the, from a pure java application, like OJ or gvSIG, so I have had to rewrite part of the GRASS interface in SEXTANTE. The SAGA one is simpler, so just a minor tweak was needed.
Anyway, I will keep on working on this, but for now SAGA algorithms are fully available, and I hope that GRASS ones will soon be as well.
Both native SEXTANTE algorithms and SAGA/GRASS ones also work within the Model Builder. I am preparing a video about that that I will post soon.
ArcGIS coupled with SEXTANTE SAGA and GRASS is really a powerful geospatial analysis app, bringing together the best of both worlds: propietary and open source. Needless to say, it makes me really happy to see that SEXTANTE is the bonding element responsible for that.