nD plotting

I'm trying to make high-dimensionality scatter plots, but I've run into a couple of issues. I'm using scatter() but including both edge and face color mapping; I doubt this will provide a meaningful display, but I'd like to try it and see.... Unfortunately, passing data arrays to facecolor and edgecolor does *not* map the data arrays to colors--instead I get gray edges and/or faces. As a side note, none of the 'usual' keyword shortcuts (ec, fc, lw for example) work with scatter().

I was also wondering if it was possible to access 'luminence' or something similar to try to map another dimension onto the plot. For some data, (x,y,size,color,luminence) would provide very meaningful ways to view five continuous dimensions.