The Channel input and boolean nodes are two of the new nodes we've added to ShaderFX 2.0.

The channel input node allows you to access 3dsMax's map channel 4 to 6 for additional vertex color inputs in case you want to use more then the vertex color channel to mix together textures for example.

The boolean node is a simple 'true or false' node that creates a checkbox in the 3dsMax material editor. You can use this to let the artist decide to use or not use certain features in your shader. For example to use a texture, or a color.