Geohot has been causing quite a disturbance due to his ongoing legal battle with Sony. Geohot jailbroke the Sony PS3 to run unsigned code. Sony is now suing him, and Geohot is under the tech industry's spotlight more than ever.
So, what does all this have to do with Windows Phone 7? Microsoft has shown interest in Geohot before, and the company even reached out to him financially for his legal fight against Sony. Geohot will know be using his hacking skills at an upcoming convention to try and jailbreak Windows Phone 7...