1 - Add a way to specify the output directory
2 - Added an option "file_extension" to control the suffix for cs files generated, defaults to ".cs"
3 - Added the option for "umbrella_namespace" used when nest_classes=false and having name conflicts
4 - Optionally remove dependencies to csharp options
5 - Investigate command line parsing library
6 - Investigate calling protoc directly
7 - Unable to resolve dependencies correctly
8 - Added several (20) nunits to automate the command-line invocation of each option

new Foo.Builder {
   RepeatedValue = { x.Select(y) }
};

... a bit like LINQ to XML.