I'm curious as to what comparisons are out there between different Open Source Desktop GIS software packages. I'm aware that there has been a QGIS and gvSIG comparison on this site but I am looking for comparisons between any OpenSource Desktop GIS.
A substantial list of Open Source GIS software can be found in response to the question: What are some Free and Open Source GIS Desktop packages
I don't expect a single comparison with everything in it, but comparative subsets. Also any comprehensive benchmark/testing that may have been performed between any grouping of these products.
Best Answer
There is a nice matrix (table) about "Matrix on OSGeo and COTS (Commercial off-the-shelf) software functionality", see this online spreadsheet. The effort of compiling the table was led by Tom McConnell, various project leads contributed to it.