Awesome script ND. 2 little things - just tested in maya 2011 and I get before each render this error:
# Error: AttributeError: ImageFormats instance has no attribute 'oldOutf' #
Not a deal breaker since the render does work w/o problems.
And also the last line should read
print ("Completed rendering of " + ($endFrame - $startFrame + 1 ) + " frames.\n");
otherwise it is saying completed one less render than it actually did (not really an issue, just a nitpick.
And I noticed if the files already exists it will ask each time if you want to overwrite it - nice feature, but might be annoying if you got a lot to render - so if you do, just delete the files beforehand.