Seems like something is up with the LiveID. I can't get anything from the marketplace, and my location services on my L900 are also down (can't get an aGPS fix). I've been trying to download an app now for over an hour and it keeps saying "We can't connect to the Marketplace right now."
This is the second time in a week that the marketplace has been screwed up. The first time the music marketplace search was not functioning and nothing could be downloaded from the store. I hope this is just some backend stuff due to the transition to the new Xbox services, but it's getting pretty annoying.