Is it a problem?
Microsoft is sponsoring Thought Thieves, a contest that asks you to make a film about “How would you feel if you saw your hard work being passed off as the property of someone else? What would you do?”
Mostly, I’d think, “Hey, cool, someone liked my stuff enough to use it.” It’s always sad when MS tries to be hip.
One thing I’ll give them — it looks like the entrants get to keep the copyright for their work. Of course, MS has reserved the right to modify this rule at any time…