I dont think he is just handing them out to anyone. I think he is looking for people are devs for creating apps. I do think this is great as it will garner more intrest in WP7. Lots of great developers out there who just have not gotten the shot....Well here is your chance!
I so suggest everyone to go follow brandon on twitter, he provides inciteful information. He was chatting to Blake Griffin yesterday about him switching to WP7. Pretty cool!
He's also giving them to "famous" people hoping for a good review, and good publicity for WP7. Even if the individuals don't like WP7, Microsoft still looks like the good guy by giving $1,000 to charity. Pretty smart idea really, very cheap advertising in comparison to a full ad campaign.