Here is a first video of SEXTANTE for ArcGIS, so you can see what it is like to access the power of SEXTANTE from the popular ESRI product. I recommend to watch full screen or at least at a larger size then the embedded video, to fully see what is going on in the screen...
As you can see, output results are not added automatically to the view (I haven't figured out how to do it yet...and this is the one single thing that I can't find documentation about...Anyone can help??), but the remaining elements of the SEXTANTE-ArcGIS interaction are already implemented and seem to be working pretty fine.
I still want to do some more testing and solve a few minor issues, but everything is going fine and the next version of SEXTANTE will for sure ship with fully-working ArcGIS bindings
We are all very excited about this development, since it means a big step in the (short but intense) history of SEXTANTE :-)