When variables are added to the gcode meta commands you will be able to use the arduino to set user variables for those fields and then write a DWC plugin to display them.
If you wanted to do that before variables are implemented you could either:
hack a work around by using fields that exist in the object model (things like settings for an axis that you did not use and was hidden).
write the file to the SD and and then have your display plugin read the file
