Sure it can!
it's just a question of time :)

you can use  some of  the GUI libraries available for processing like controlP5 or GUI4Processing http://www.lagers.org.uk/g4p/index.html for example

Thanks for the replys. Now I ask how you would organize something like this, with C everything is layed out into folders and across multiple .c files, it doesn't appear that the Processing environment can do this. Is everything going to be in one, big page?

processing was built to keep it simple. so in the case you want to go with the processing IDE you still have the option to create new tabs. use the icon in the right upper corner.
Another idea would be to use some IDE like Eclipse : http://processing.org/learning/eclipse/