Microsoft has filed broad patents covering the .NET API. It appears that they are attempting to patent the relationships between namespaces (client programming versus XML manipulation versus network transport, etc.). At this broad level, the patent should be rejected on the basis that the particular separation of concerns noted is obvious "to one of ordinary skills in the art." Reading the entire patent, though, although the claims relate to very obvious high-level relationships, the supporting documents mention every single namespace in the .NET Framework -- as if the specific patent is for the admittedly non-obvious web of relationships between all the namespaces, a claim that should be rejected on the basis of operativeness. Operativeness is something like a negative proof -- if an invention that does not implement the exact structure is useful to the extent of the claims, the invention is not patentable. For example, you can patent a new design for fastening sheets of paper, but you can't patent an obvious paperclip design in which the paperclips are blue (unless you specifically make claims about the usefulness of blue-ness).
This is a bad patent and should be rejected. Let's see if the \$1B per year spent on patent review does the job this time...