[I did try to track the licence details down, but the MS Partner site requires IE, which just crashed my puter, so I gave up. I believe the licence is different.]
But isn't this a bit off-topic? My point was that not everyone has access to full VS, even given the WebsiteSpark thing - that's true whatever the details of your and my licences. Those people may wish to use VS Express to program Arduino, and currently it isn't the easiest thing in the world to do.
Chris.