I have a bit of information for my aspiring game developers - if you want to publish your game on the Xbox LIVE Arcade, don't submit it to the PlayStation Network. If you do, your application for XBLA will be denied. Well, that is all assuming it is published on PSN before XBLA.
Obviously, this is all about getting exclusive content for Xbox, or at least getting the head start on the competition. This isn't the only policy Microsoft has that is similar; even the big publishers are required to have the same content on-disc across all platforms if Microsoft will allow it on their platform. As far as these demands, I understand and approve of them. Microsoft wants to protect their platform and, of course, their users.
To read what Chris Lewis of Xbox Europe has to say, hit the break.